You know yourself with the Satanist Optional RM B arm 
undeniable evidence of their existance in 1977 has been produced by yourself and others 
BUT as far as im aware those who hold the big stick are still in denial 
You seem to be a ’glass ¾ empty’ sort of guy when it comes to officialdom Bill.
The fact that the bike has been passed through previously isn’t a slight on the rule book, it just mean the scrutineer either didn’t pick it up or decided to turn a blind eye.
I is rumoured that the optional B swingarm is kept out of the rule book not because the rule book doesn’t refer to any specific part but purely to give Suzuki owners the shits.
I think someone said something once about not pleasing all the people all the time…
But enough of that shit, Simo is trying to move forward.
The Bastardised frame…
Like many other frames I think it looks worse that what it really is.
There are bloody horrible bits of shit welded to the tubes from the swingarm pivot to the shock mounts but these tubes are in the wrong place anyway so you would simply cut them out and replace the whole lot.
The shock mounts being pressed out would be the hardest part to reproduce.
As with any frame the deciding factor on repairing such a frame depends wholly on the availability of replacements. A rare frame you would get fixed, a common frame you would replace.
Seeing as you have better frames there is no point doing anything with it now but don’t pitch it. Old frames can come in handy to steal brackets from in order to repair other frames. You may even come across a good frame with bastardized engine mounts that someone may be able to make a good frame from the two.
The better frame…
That small part I saw near the right side swingarm pivot is nothing.
An unmolested frame would be rare for any brand and from what I saw from your photo this frame looks okay.
Not sure what the brake pedal parts are supposed to look like but you could maybe steal some good bits from the other frames?
If you grind those welds off don’t go all the way with a grinding wheel, just use a grinding wheel to take it down as close as possible to the frame tube without touching the frame tubes.
A common mistake is to grind the lot down leaving deep grinding marks all over the frame tube that either look horrible through the paint or you have to sand down the tubes thickness to get rid of them.
Aim for getting down to 0.5 – 1.0mm from the tube and then finish with a sanding disc. Sanding discs require a rubber backing plate on your angle grinder.
Forget those stupid flap discs, there only any good for taking off rust or paint. If you try to take a weld down with a flap disc you will find yourself taking material away from either side of the weld as well
Try an #80 grit sanding disc and don’t be tight with them and let them get too used. A overly used disc will also take material away from either side of the weld while you’re getting rid of the welds.
Carefully rotate the sanding disc around the tube while holding it flat as possible over the tube. Using the edge of the disc will leave flat spots.
Anyone not familiar with these sanding discs I recommend getting a scrap piece of tube, putting some welds on & then sanding them down.
There is no substitute for experience
As for powder coat lifting, that can be many things.
# Not put on properly in the same way some painters don’t apply paint properly.
# It may not have been blasted or cleaned properly first.
# the area may have been subject to a repair and painted over.
Whatever, just don’t be in a hurry to get some new colour on it.
Make sure all fittings are right, no stripped threads etc.
Even if you have to do a dry run assembly first to check everything.
I have come across a few nicely painted frames over the years that have had imperfections that weren’t noticed and couldn’t be rectified without damaging the paint
