early upper arms were 4 bolt. The design was “cheapened” by minimizing the steel around the 4 holes. This led to cracks & issues. The 3 bolt was a redesign. These were riveted. You can swap 3 & 4 bolt arms.
The 67 lower arm is different due to the articulated strut. ( the holes in the arms are closer together). Suggestions are to swap to 68+ style. New repop strut rods & Moog (all Moog parts strongly recommended) lower arms.
Front sway bar. The bigger is not always better. Upto 1" is probably ok, but any more the car will push in the corners & not turn well. Requires a rear bar. Take a lok at the vids of my 69 RestoMod on the track. Has all original style suspension. A few mods & it handles…
Hope this helps save a lot of $$$ on items not needed or helpful.