As far as I know, the T90D is for the 1966-1968, K0's, also the T90A, T90DS & 572A carbs have been found on the K0's.
All are 4 screw bowl carbs with a "flat", rectangular bowl gasket.

I don't have the T120A carb as being used on a CT90, I don't know what it is used on.

Maybe I'll learn something.

Paved roads, just more needless government spending...

I pick up my mail in Santa Barbara, California, USA.