Frame is throwing me for a loop (PICS) CB750K

[JBW5]

I have been working on this 1978 cb750K for about a week now and I noticed today that the rear tire seems to sit a little to the left.. I thought the wheel might be out of true but when i spin it it remains consistent. The thing is, it is clearly centered on the swing arm and I took the shocks off and put them back on and they seem to line up fine.. Im thinking maybe the seat rail is tweeked but I cant see anywhere that it looks tweeked? also the frame looks square in the front when looking down on the heads! Thanks for any advice or input! Im kinda stumped..

 

[Clint]

Looks to me like the adjustments at the swing arm and the wheel need adjusting.

 

[dirtdigger]

Are the swingarm bushings worn causing the swingarm to shift to the side?

 

[cyclebuster]

wrong shims its off center.