Small block to big block trans cross member doesn't work after swap?

Bobzilla said
Couple things going on here and you need to be very clear about the front end of the trans and where it’s hitting. Also show some pictures of that.
I can see in the third and fourth pictures of your original post that you have a later truck style output housing, the part your insulator is bolted to. I have that same housing and trans crossmember currently installed in my A-body, although mine is a small block right now, and is a later 1975 model year.
I previously had this same crossmember and insulator, and the same driveshaft with my previous big and 727 trans in this same 75 A-body.
I will add a picture of my crossmember, although it’s from a different angle so hard to compare for sure, but shows yours is installed correctly.

View attachment 1715792560

Here is a picture on the driver's side of where it was hitting. It's the body seam, rubbing some black paint off. I fabricated the ears on the spool rubber mount to extend it about 1" - 1.5", moving the trans away from the firewall. This will at least get me real close to where it should be.

If anyone else has a barracuda with a big block that could give me some type of measurement from the mounting surface of the trans to the firewall that would be very helpful.