I lost the rabbit

Distributor was out, engine was turned.

If you bring #1 up to TDC, how can you tell if it's compression/power or exhaust/intake ?

Blow air in and listen for leaks out the valves ?

Engine is all together.

Pull the spark plug. Put your finger over the spark plug hole and have someone turn the crank over. When the piston is coming up and it's coming up to TDC you'll feel air trying to escape from under your finger.

Unless I'm mistaken, if it's a B/RB/Hemi you should be able to see the lifters for #1 cylinder through the distributor hole. A/LA/Early Hemi/Poly, I've never had much luck with the finger in the spark plug hole with a fresh motor. Off with the valve cover.

On the ex/in stroke the exhaust valve closes after TDC and the intake opens before TDC so there won't be much pressure to feel at the plug hole. But on the comp/ign stroke both valves are closed at TDC so the pressure will blow your finger out of the hole.

And would suggest having someone "bump" the starter with the key or use a remote starter switch. As it starts to come up you'll fell the compression as mentioned. keep bumping it while watching for the timing mark as it approaches TDC while bumping.
if you go too far, you will have to rotate the crank almost twice to get back to to the compression stroke.

I took the valve cover off, I think it was leaking anyway.

I have to say, this is a 360 in a 79 D150 half ton. A small block in a truck.

AND THE F-N VALVE COVER ALMOST DIDN'T CLEAR THE BRAKE BOOSTER.

A small block in a truck, not a Hemi in an A-body.

Sheeesh.

Can barely reach the distributor, need scaffolding to stand on.

I found it easiest to sit on the inner fender with my feet on the framerails while working on my '75 Powerwagon.