No reverse

I just went to test drive my '81 4speed after 5 months of work on it - Including rebuilding the rear suspension and installing a set of headers. I did some other minor changes and upgrades - none of which included the transmission. Except for the installation of a urethane trans mount. Now I find I can't shift into reverse. The lockout works -in fact I can take the rod out and still can't get reverse. I can move the reverse linkage manually into two positions - neither of which give me reverse gear. Can anyone give me some ideas? Thanks.

You move the linkage manually, but are you sure it's going all the way? It may be traveling but not far enough. Rotate the drive shaft a bit while trying to move the linkage. Or perhaps drive the car forward a bit then try reverse. It sounds like something is not lined up inside, and a bit or rotation may help.

Well, OK - I do get reverse gear if I move the linkage manually. I can see now that the bottom of the shifter (which is supposed to kick the lever back that operates the linkage) does not move far enough to the right (passenger's side) to engage the reverse lever. Something is stopping it. Could it have something to do with the reverse interlock? Like I said, I have touched nothing on the trans except replacing the mount. I can't see anything stopping the shifter's travel. I haven't gone in from the top yet - I guess that's next.

Jim I just changed my mount and I'm now having a hard time getting into first gear. I can't see where, but somewhere I must have bent the linkage when I jacked up the transmission.
I was under the car today and can't see anything wrong...but somewhere......
good luck

Thanks for the info. Since the mount's the only thing that changed - it's worth taking a look at. Maybe put the old one back in if I can find it. I'll let you know what I find out.

Here's what I found - I loosened the new trans mount and jacked up the trans. I took out the exhaust bracket for the original exhaust - it was just acting as a spacer at this point. I let the trans back down and voila! The trans shifts into all gears smooth as ever. It must have to do with the height of the new mount vs old mount throwing off the geometry of trans and linkage just enough. Who'd a thought? Hope this helps.