Got me a new truck with a slant Six, what should I do?

I can't tell for sure from the pictures, but that might not be the original engine. 1981 should have hyraulic lifters. Earlier should be solids. If a solid lifter engine, and you wanted a little more power, I would mill the head to get an "honest" 8.5 to 9.0 to 1 compression, and add a two bbl manifold and carb. Make sure the exhaust is 2 1/4 inch from the manifold back. No down side to any of this. It will help power and economy, both.
If it is a hydraulic lifter engine, you can do the same things, but it gets a little more involved with the valve train.
Edit: As cheif noted, no vacuum to the distributer. It might have a distributer with no advance mechanism. Swap that out for a distributer with centrifical, and vacuum advance.

Or you can bring it up and donate it to me :) :)