Properly done plasti dip looks very good. If you are seeing imperfections it is because it wasn't applied properly, The wheels I did with a base coat and a glossifier, on my wife's car were indistinguishable from painted wheels until you touched them and realised they felt rubbery.
A stock Busa has adjusting screws that push the adjuster blocks back to tension the chain. It looks like the aftermarket arm on your bike has pull adjusters like some dirt bikes have. The blocks you bought are not compatible with the swingarm you have from what I see in the pictures.
If I could own one collector vehicle it would be a '70 Boss 302. Ya, I know there are much better driving cars with better brakes, that accelerate faster, however I have wanted one of these cars for 25+ years.
I have found that it is often less money to get a motorcycle that is good running condition in the long run. However the 250 has sentimental value to you, grab it and fix it up how tyou you like, the 700, it might be best to leave it.