Initially I was just going to repair the wheel arch by putting a new skin on but when I started cutting I discovered corrosion that would necesitate the replacement of the complete wheel arch and step.
Now, as Spooky is a 'hybrid' bus all bus owners can benefit from this description as he has a small step but has the flared lip to the wheel arch. As most people will know, you cannot buy complete arches for these buss's so you need to buy the 73 - 79 wheel arch and cut the step down to fit. Owners of pre 72 bus's would not need to do this as the repair panel has the small step and the flat arch.

You can see from the picture above that the seat belt anchor had at some time been 'repaired', if you can call it that. I bought the proper Scofield repair plate from John at QB which can be seen in this shot.

You can see in this shot where the inner and middle sills had been fitted, together with the front jacking point and outrigger. In order to complete the sill repairs, the B pillar needs to be repaired. Here you can see the extent of the corrosion of the B pillar. You can also see the amount of the seat bulkhead that was removed.

You can see now why the complete arch needed to be replaced.

Here you can see what that horrible patch covered up, I've also cut out that patch on the seat bulkhead, talk about 'string of pearls' welding.

Here you can see where I have cut away the rest of the rear part of the wheel arch, the front and outer part of the B pillar. I have cut the B pillar repair to the correct length (thats a Scholfield repair section) and got it offered up. I've also offered up the outer sill to make sure that the profile is correct.

Here you can see the repair patch (home made) used to repair the side of the B pillar and the reinforcment plate running up from the inner sill up to the floor.

I have now made up all the plates to repair the bulkhead prior to fitting the B pillar, I painted the inside of the B pillar before welding. Even though the welding process will probably burn off some of the paint, I plan to get some WaxOyl in there when it's finished.

The B pillar repair has been welded on and the closing panel fitted. You can see the two holes in the bottom of this panel which allow access to the inner sill voids for WaxOyl and inspection. These will of course have grommets fitted which will be sealed with seam sealer so that they wont leak water into the void but will allow me to remove them for inspection in the future.

Here you can see that I have started to cut away the old wheel arch and trimmed up the area where the new seatbelt anchor repair plate is going.
I tend to be a bit carefull when cutting so that I don't make any mistakes and I know how it's all going to go back together.

I have put a bracing strut across the door aperture to ensure the door surround does not distort. This is just a rod with a threaded rod welded to one end and a hook welded to the other, it hooks around the A pillar and goes through a hole drilled in the bulkhead and through a 1/4" piece of steel where it can be tightened until the door closes nicely.
I have also cut away the step area.

Here we can see the corrosion damage to the A pillar so it will need to be repaired which can be seen in the next picture.

Cut away the damage and clean up.

The repair to the A pillar

Here we can see that the whole area has been cut away and cleaned up ready to prepare the new wheel arch for welding.

Ok, heres the first attempt and what you cannot see from here is the fact that the arch is the wrong shape, it's definately not easy to see but believe me it's wrong. If I had welded this into place as it was the door would never shut.

So here is how to get it right, turn the door upside down and bend and shove until the profile is the same. This arch had a huge gap at the step end so I kept on putting my weight in the actual wheel arch area to open it up. Then I would offer it back up to the door until I was happy.

With the pre 73 bus's the front bumper has these steps which attach to the underside of the wheelarch 'step' so a method of attachment has to be made.
Also you can (as far as I know) only buy repair wheelarches for the post 73 bus's which have a deeper step which needs to be cut away to fit the earlier profile.
Here I have fitted the bumber and step and have marked the bolt holes on the underside of the wheelarch.

Into the workshop and here I've cut a hole where the step attachment bolts will come through. I have made up a small panel that will be riveted over this hole after the bumper is fitted and the nuts Waxoyled. This also means that the bumper step can be removed in the future.

Here I have drilled a hole for Waxoyling, it will be fitted with a grommet so access in the future is no problem.

I've now started to tack the new arch into place, but as I did not trust the overall shape I only tacked it at the front where I know the position is correct.

At the rear I have put in a gripper pin initially to line up the outer edge with the B pillar and once happy tacked it there. In order to make sure the arch was the same profile as the door I fitted the door and shut it putting a small piece of packing between the door and the wheel arch so that it pushed the arch in 'too far'. I then did a couple of small tacks underneath and then opened the door, removed the packing and tried closing the door a couple of times. As soon as I was happy I then made some more serious tacks.

Here I've put a few tacks under the step area and you can also see where the access panel comes in.

Here I've tacked in the seatbelt anchor repair plate.

And here it is all nicely welded into place. I carried on welding in nice short sections all around the new wheel arch both inside and out until the whole thing had been done. I made up small repair plates where the sections joined like where the B pillar joins the top of the arch by the seatbelt anchor.

These three pictures show the welding complete, the first coat of primer on with the seam sealer on all welds and any places where there is s gap. In particular you will see that where the door seal contacts the wheel arch is where the new arch has a spot welded join, this has got to be sorted out as the door seal will retain moisture and it will leap in through that gap and start the whole rotting process all over again. Just get tons of seam sealer on there.

So there you go, how to replace a wheelarch