[Palf70Step]

Far as I know the OBS (88-98) are not an easy swap. I believe it is because the width of the frame rails is very different (OBS is wider I believe). On my old 70 I used 78 Spindles, brakes, ball joints, Tie rod ends (inner and outer), crosslink, idler arm, and pitman arm (I was also going from manual to power steering) with the stock 70 A-arms. Came together great and had all easy to find stock parts (and all are 78 so it made it easy to remember when /if I ever need replacements. You can easily swap the entire front cross member of a squarebody to get the later style A-arms (I prefer the older grease-able one). If you do the entire cross member there are a couple holes in the cross member you have to wallow out to bolt onto the 70 frame. I don't remember which ones, but you should find it here on the board.

Again I don't think the 88-98 style will work without a bunch of mods.