I simo posted over on the drivetrain forum. You're both exactly right, THANKS! In the process of checking this out a few days ago, yanked the speedo gear housing and discovered the entire inner seal was never installed by the "rock star" that rebuilt the trans. Well, ya buy one at a swap meet and ya takes yer chances! Still tickled pink with the trans, this was a $6 fix. Now good to go. Pics below if anyone interested. Thanks for the replies folks, much appreciated!
Markeb01, the guy that was sellin it at the swap meet said he installed the mech speedo gear hsg - it was originally an electronic hookup for a 93 trans.
Interestingly enough, when I pulled the hsg, only a dribble came - probably because it had all leaked out already! But low point in housing is only about "1/3 quart" below the fill hole, so at least I didn't take another ATF bath. Didn't even need to go to the parts store for more fluid either.
And again, both correct - all fluid should remain inside the trans if both seals working correctly, even if no cable installed - and it should never leak into the cable - but will if the small seal is shot. A little got into mine, but mostly just dribbled onto the floor - not my feet, luckily. Whew!
Now, if I could just finish plumbing my brake lines, I could this this thing on the road!
http://67-72chevytrucks.com/vboard/s...d.php?t=484616