when recently putting my new engine and side-shifter into my '72:

I pulled the old(tail-shifter) linkage out, ( I thought I got all of it anyway...)
I used a "press" (long bolt/nut with very large washers) to put the firewall bushing in... only to realize I had to pull the bushing off again because I left a rod in the tunnel (doh!) it came out easy and went back easy... then I went to put the side-shift linkage together... only to realize I had to pull this bushing AGAIN to put the front shift rod in... I also noticed that the shift rod fit the bushing very tight! I know I am using the right bushing (one made to put a side-shifter into a pre-'73 car) but I'm afraid that by pulling the bushing and putting it in too many times, I've damaged it... do I need another one before I put the linkage in?

You get a lot more leverage to move the shift rod when you use the gear shift lever. As long as it isn't really sticking in the bushing, and as long as it doesn't pop out of the firewall hole, you should be fine.

You did look at the bushing before you re-installed it each time, yes? Just a quick glance to make sure you didn't break some part off of it?

--DD

yes, it looked ok, but was seemed tight on the rod, and much looser on the firewall...

thanks, I'll keep a watch on it for sticking and popping off...