100 psi in all cyl's is good enough fire and you're thinking is right re. adjusting the valves.

Looks like you've got compression and fuel sufficient enough for starting and running. The ign system is next.

Verify spark at the plugs. I recommend one of those $5-$10 spark checkers from a FLAPS as they always come in handy and you don't have to hold and crank.
An easy test for spark is to hand turn the engine until the points are closed.
Disconnect the coil lead from the distributor and either connect the spark tester and plug to that lead, making sure the plug is grounded or hold the lead to within 1/4" or so to ground (with insulated pliers etc).
Turn ign swtch on
Using a ty-rap, straw, small stick etc, push the points open and observe for a spark at the coil lead. Every time you allow the points to close then open them up the coil should produce a spark.
Next would be to verify timing.

Let us know.

1949 Chevy 1/2-Ton 3100
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