I know you are supposed to leave the upper control arms nuts loose and then jack up the car from the lower control arm then tighten. Not sure if you did this.
Yep that will definitely intensify the squeaking. @Cam1399 Get it to ride height 'loaded' then tighten the uppers. If it's getting aligned those will get loosened up and reset anyways. I like polyurethane in my old cars especially the lower arms doesn't matter if the upper arm so much really helps on the strut rods a lot when it comes to turning. Squeaking doesn't bother me at all because I know why it's squeaking and that makes me feel good knowing it's a great handling car it's not going to get bounced all over the ******* road. The quietest combination for using any polyurethane bushing would be to use them in the lower arms only and strut rods and use rubber in the upper. In the rear use a rubber big eye bushing in the spring and use polyurethane 1" shackle bushings.