do i need to replace my whole rear control arm or can i replace just the bushings. ?
i had my car on a lift as i was getting a new rs dual 3'' exaust welded on and the guy pointed out to me that the bushing is all chewed up and rusted on one side of the back passanger side control arm. it looks las if rats were chewing on a donout. he does not do that kinda of work nor did he recomend anybody to do it but he stated that to his knowledge he believes i have to replace the whole control arm and he said i can not replace just the bushing as its all one peice. can anyone please help as i was quoted $350 to replace the rear control arm but i was also quoted $100 from another mechanic who said he will replace my whole back of the car meaning both rear control arm bushings for the $100....
i was also told that if i dont replace the bushing or the rear control arm that, that side of the car in the back where the bushing is damaged can cause that side of the back of my car to collapse and sag to the ground.. can anyone help me on this.. thanks

You can do just the bushing but it'* very hard without a press. You have to slide supports into the middle of the arm to support the metal and press it out. Compared to the labor costs if you're going with the mechanics you've already talked to just get the new arm. If you want to find a mechanic who knows how to do it then use them.