The T-56 is a pretty big transmission. The recommended way to install it is to cut & raise the transmission tunnel 1". This is true even in the larger '67 & '68's.

Dark Horse Performance sells kits that have the option to use a lower mounting transmission cross-member to avoid having to cut the tunnel. But, I've been told by others that you really don't want to pursue that method. Best to mount it up where it's supposed to be.
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