'69 Barracuda T56 swap, floor, cross member

agreed, you'd only need 1/4-1/2" so the torsion bars will be fine. to check just loosen the bolts and slip in some c shaped plywood spacers. once you know it works make up some steel spacers, remove one bolt at a time and fit them. if the trans needs lowering slot the crossmember bolts til you're happy then weld washers to it to cover the slots.
it's only metal, lol.
neil.
Been reading on k frame spacers most ppl say up to 1/2" with an alignment and its fine. Apparently its commonly done by many people with no adverse side affects.

I am going to check engine/trans and pinion angles next. Then maybe temp space that k frame like you suggest and recheck angles. But yeah just 3/8" or so lower I think I can get the required clearance.