OK added an 80's cb650 swingarm to replace the stock one...
here's a size comparison w/ my friend's cb750 custom (which is essentially the same except for 1/2 extra width at the pivot.
It looks positively MONSTROUS compared to the stock one, but it looks great on the bike



Here it is on the initial test fit:

Side by side comparison:


(before) pic looks like the wheel is trying to shove itself up the bike's butt unlike the (after) pic which stretches it out..plenty of space.
It moved the shock mount back by 3" from eye to eye.
Unlike the 750F or Custom arms ...this one is an exact fit on the width. The only mounting issue stems from the fact it uses a slightly thicker (about 3/32" ) thicker pivot rod/bolt). I've read on other threads where they bored out the hole on the frame slightly bigger, but I am not about to drill a hole in mine (not yet anyway). I'd rather find a workable BUSHING that will fit in the 650 Arm and allow the use of my stock 750k bolt.

Here it is again (mocked up) with the oil tank and exhaust and my (finally) repaired front wheel (tube was flat).
The spare (chrome wheel) in the other pic had a much beefier tire on it than the black one so the black wheel removed some of the front Rake it had.



TONS more clearance now. Could fit a much bigger wheel tire combo if desired (but not now).