When you pull the dipstick what does the oil look like? If it’s not milky or sludgy you can run the engine for a few minutes enough to warm the oil before you change it.
Before you crank or try to start the engine I would prime the engine oiling system. This would can be done by removing the distributor and using an electric drill and priming shaft. You can make one from an old distributor by removing the shaft and grinding of the cam drive gear. Run the drill for a couple minutes after you show oil pressure. This will lube all the bearing surfaces before you put a load on them. I think Chevy distributors turn clockwise, the opposite directions of Pontiac. If you Google this process you can see online videos of how to.
I would pull all the plugs and give each cylinder a little shot of engine oil. Just a little bit, you don’t want to have hydraulic lock. Once you put the distributor back in, crank the engine over a few times before installing the plugs to lube the cylinders.
Once you put the plugs back in you can try to start it by pouring a small amount of fuel down the carb. If it starts, you can see if it will run off the old fuel in the tank. It’s possible you will have to drain the tank and clean the carb.
Oops, sorry I did not see Blackbirds post.
