Anyone out there with knowledge or shop manual information for  4-speed transmission linkage adjustment on  a  "80" ??. I ordered a linkage rebuild kit from ZIP along with a linkage guage , but will probably need the linkage adjusment procedures.

Soitainly!!
Check out This thread!

Joel, thanks good buddy. I'll give it a try this weekend and let you know how it went.  Thanks again

Joel,  is the linkage adjustment even possible from underneath??. Looked at the underbelly yesterday and seems like real tight quarters to make even minor adjustments. Would removing the console make for easier access??

It is really tight up in there, for sure!
If you have the original GM shifter, the adjustment "slot" will be on the very top surface of the shifter. On your '80 car, it may be easier to get it from the top, but I couldn't say positively. If you take the side/top console panels off, and the shifter boot, you will probably be able to get right to it.
I will say that doing pretty much anything with the shifter while laying on your back it gonna be rough, unless you have really small hands, AND are a contortionist!
With a car on a lift, it is more accessible, but....not everyone has a lift.

Sooooooo!  ham-hock hands and an inflexible body is definetly not an advantage ? . I will   attempt from the top and see where that goes. Thanks  Joel for your input.

[QUOTE=ddog] Sooooooo!  ham-hock hands and an inflexible body is definetly not an advantage ?[/QUOTE]

Only on motorhomes, dog....only on motorhomes....