Mechanically, this was a pretty low effort swap... most everything had been previously installed in a 510, I wasn't attempting anything fancy, and the SR fits so naturally.
Starting with the mounts...
Motor mounts consisted of 1/2" spacers. Yup, that's it. I machined 1/2" aluminum spacers and used the stock L-series rubber isolators. With the spacers, the SR bolts up to the stock cross-member. Well... kind of. The issue is not the mounts, so much as the cross-member itself. The SR being a front sump, created a bit of interference. This has been addressed in several different ways, but I chose to cut out the front biased offset and weld in a 'straight' replacement. I think a single 2" round tube would have been sufficient for any normal loads imposed, but I like to be able to jack the car up by the cross-member. This led to using 2"x1" box tube, one situated vertically, and the other horizontally. This seems to be plenty stout as jacking produces no visible deflection.
The transmission mount is a modified stocker. It ain't pretty, but its stout. I cut out the center, welded in a 2"x1" box tube (horizontally) and drilled a single hole through the center. I used a GM transmission isolator, which fits the SR tranny nicely (Energy Suspension part# 3-1108G).