What is a good cold valve lash to set this 63 292 at to get it started and wormed up? Then I can do the correct hot adjustment.

 

Spec is .019 (cold) in manual or near enough but search the archives there are some good methods. I like the 1/4 turn and done method, outlined specifically for Y blocks. This takes into account wear and slop in the valve train and is easier and quicker. Setting by ear works too.

The exhaust design of Y blocks doesn't really lend itself to setting when hot, the feeler gage is a PITA.