The upper control arms are a little more involved. If you try to press both bushings in without supporting the inner arms where the flanges are, it will bend the entire arm in half and destroy it. Originally there was a dealer issued tool (no longer available) that supported the area between the two arms while using a press. So I built my own...
First, I used the vice to press in the smaller bushing (1975 used a large and a small bushing, while earlier models used the same small bushing on both sides). I then set the pivot bar in place, passing it through the larger bushing hole and set the large bushing in place. I then set up the spacer bar I fabricated from the old central pivot bar that I had to cut off due to the factory spot weld. I cut it to the exact length that could run parallel to the new bar. This way I could use a couple long bolts to pin them together to hold the spacer bar from flying outward under pressure. It worked great!