Fuel pressure was at 10 psi, which seems high. Everything I have read says 6-7 psi. Could this be my problem? I am still running the manual fuel pump. Oh, also I re-checked the initial timing and what I thought was a 9 was actually a 0. So initial timing set at 10.
Ok 10 is reasonable for initial timing.
10 for the pump is ok might seem higher then usual but the gauge reading may not be 100% correct.
18 in park is good. Dropping to 13, try turning the bleeds 1/8 a turn counter clockwise to open them and see if in gear the vacuum starts to come up.
I would want to know gapping on the plugs, making sure you don't have weak spark.
Also disconnect vaccum accesories for testing and see if you have a gain in vacuum that would indicate a small leak or other issue.
As for the engine cutting out. Try to make it reproducible.
For example does it only do it when you heavily accelerate. If your light on the pedal and it doesn't happen then we need to see if you are rich or lean.
So say you punch it, the car starts to go, then bogs maybe it stalls and you see black smoke then you know too rich.
Say you punch it the car pops from under the hood and you stall out, too lean. Your getting carb backfire.
Now with rich you can try advancing the initial timing to 12 and see if it improves.
With lean back off timing to 8 and see if it improves.
Either will take you in different tuning directions. Lean means your going to be playing with shooters, accelerator pumps or power valves and making them flow more fuel. Rich means your going to change things to flow less fuel.
Another thing is checking to see if the problem stops when the vacuum advance is plug and not working. You want to do testing just on mechanical advance.
The mechanical advance is another area that should be looked at. While in the distributor you check if your running points or electronic ignition.
Under that is the mechanical advance and you want to see if somebody messed with it. Sometimes people change the oem springs on the mechanical to gain performance. They install a lighter spring set which might bring in too much timing to fast leading to a lean power stroke and carb backfire. Oem is one heavy spring 1 light spring both silver color, A mr gasket set would be 2 black colored light springs, or sometimes people just leave one light spring. If you find a situation like that you might want to get a new set of springs. Sometimes one of the springs is found to be broken or it fell off inside so you never know till you inspect it.
As for low vacuum. Weak spark can cause it or delayed spark because of aftermarket wires which mechanically throws off timing and makes the engine seem retarded in spark. A vaccum leak could still be at play,idle might be too low, or again changing the idle bleeds richness under load.