I'm not an ES expert but I thought I'd chime in. Check your ball joints! The last car I drove that had stiff, stiff steering dropped a lower ball joint just two days later. I aggree with the post about caster, if the BJ's check out okay, get a good alignment. Find a shop that is willing to mess with crossmember shims. The perfect alignment has the same amount of shims, fore and aft, on the upper A-arm "dogbones" regardless of the count, side to side, between frame and crossmember.

Vacuum retard is great. I have a set of SU's that tend to idle high and when I converted to a '75 Bosch ignition, introducing the retard to the system brought the idle right down. 10-12 degrees BTDC with the vaccum line disconnected(from distributor)and plugged. when you reconnect the line it'll drop your timing to somwhere between 0-2. The theory is; vacuum only occurs at idle and decompression so I guess it saves gas. I agree about the "vacuum ADVANCE mis-conception"-it's rampant:o)
Thanks for letting me addtoit.
Shayne.
'64 220, '66 130, '76 124CS.