I have an 80 with the L-82 and i was wondering what size valves i have.

and possibly rear end gears but from what i understand there was about six rear end options

 

I'm guessin' valves are 1.94's.
Rear end.....
get one rear wheel off the ground, leave trans in neutral.
Mark the drive shaft and the rearend housing at a common point.
Rotate the tire one full rotation and count the rotations of the drive shaft.
This will get you real close as to the ratio of your rear end.
3 turns, 3.07:1
4 turns, 4.11:1
These are rough numbers, but will get you in the ball park.