First thing I would do is pull the oil dipstick and make sure it's not being contaminated with fuel.
Visual the entire fuel line for any sign of leakage.
Make sure the choke is working properly.
Maybe check part sites such as Vans Auto. Individual parts may provide a clue for a better application search.
https://vansauto.com/product-category/transmission/
Might be worth driving it in a straight line and check what the bearing housing ends measure in temperature for a clue.
Spring eye bushings, shackle bushings, mounts, U-bolts and spring alignment pin.
I have seen only one loose axle tube on an 8-3/4 over the years. But ya' gots ta' check...
Appears to be an OD per the shift tab orientation.
I believe the trans in the picture will fit an E body dependent on bell / trans input retainer size and output spline count for the driveshaft.
Another issue would be whether or not the crankshaft is drilled for the trans input.
The shifter is...
Top right....
Click the Letter to the left of the bell and choose "Show all".......
Conversation list displays.... click the box for the ones you want to leave...
Bottom left....click Choose action....a list displays.........choose Leave conversations....
Click Go...............
Likely not but one never knows unless it's been confirmed by previous work and documented. The numbers you post won't tell ya'.
Some auto cranks were drilled to depth but not finished for the bushing. Others just have a center drilled.
Rather than drilling the crank, many just use the converter...