I have had problems with the front end sheet metal getting out of alignment. The subframe bushings are shot I'm thinking this may be causing the front end to shift. In additional the subframe was was not properly aligned . In order to align the subframe I have to remove all the front end. Just hope I can get it all back auto gather. The front end is and engineering nightmare.
Your post is not clear about this but have you actually removed the front end yet? If not, hold off as you can replace the body bushings and align/tweak the subframe without removing the front end sheet metal.
Bowties are for Pee-wee Herman. "Chevy": even the name sounds cheap, but not as cheap as your Pontiac will be with an LS transplant.
Too late front end is off. When I said alignment I meant the holes in the body that are used to align the subframe to the body. I made pins for them. One side is off about 1/16th and the other about1/8th. Shifting the subframe around with out loosening all that sheet metal would have been difficult. You are correct about being able to change subframe bushings without removing sheet metal. A problem I have been having is the grill assembly has been shifting to the passenger side. I have corrected it twice. It gets quite noticeable. The center subframe bushings were replaced by the PO. However he didn't replace the rear ones They are severely degraded. I have new bushings from Global West that they ship with their subframe connectors
Now that the front end sheet metal is off I can see the misalignment of the subframe is about 1/4 inch one side about 3/16th inch the other. Previous owner when he changed the sub frame bushings he only replaced the top center ones the bottom of the center bushings are squashed out as is the whole assembly on the rears. It also looks like the center bushings have been moving.