Fuel delivery issues

Dana67Dart said
If you are refering to the valve that goes between the vacuum hose and the booster that would not produce the pedal to the floor that you experianced. The external valve only keeps vacuum in the canister. There is some valving inside the booster that must be malfunctioning.

As long as you have a vented gas cap, capping them should not be an issue, as well as leaving them un capped for the moment( other than insects and dirt and moisture and fuel vapors)
If you think you are pulling a vacuum in the tank leave the gas cap off while testing

Ok, I'll leave the cap off for now then. Still stuck at work but hopefully done soon with a little bit of time left to work on it some more tonight. If the booster is shot, it's probably going to be later this week then before I can get a replacement so I can drive it. I also still have to figure out the overheating issue on the driver side. The heads were sizzling and I only ran it for a handful of minutes so there's some serious lack of coolant movement going on there, not sure why but that'll need addressing as well.