Sorry about the delay and any repetition, and please be patient with me while I try to get updated...
Sandblasted subframe:
SPL Pro Aluminum bushings in the freezer overnight:
Heating the subframe after unsuccessfully trying to hammer the bishes in:
Trying the vice method since heating took too long:

After talking to Estevan(NOSTALGIC HERO) on FA, I realized that using large washers, studs, and nuts with an impact and a wrench would have been easier...
All 8 pieces (4 sets) in the subframe:

Note the discoloration from heating.
After blasting the subframe again, I painted it with some black epoxy spray paint:

Pretty, huh?