64 C20 with 73-87 Front end Swap Question

['64C20]

So I swapped a 73-87 C10 front end under my C20. I initially did this because I thought it would be cheaper than buying the 8-lug disc brake kit.

Anyways, now that everything is in, the trans mount for the SM420 bell housing is off by maybe an inch or so. I utilized the clamshells instead of the pedestals due to the fact that I want to swap a big block into it in the future.

Has anyone run into this? Idea was to use an adjustable trans mount and make a plate for the back of the trans.