Engine dies when hot, in gear
put a clear fuel filter in line and looks like the fuel is bubbling in the filter
Since you have fuel in the filter, and pressure, the pump is fine. Fuel vapor bubbles will not form at pressure. So the question is, what are the bubbles?
My guess is that the pump is sucking air.
There is a hose-jumper at EACH end of the hard line.
The front one usually leaks if it is not tight.
But the back one is above the liquid in the tank, so it does NOT leak. But the pump can easily suck air there. Replace the hose, and reuse the factory spring clamps. If you do not have the factory clamps, and are forced to use gear-clamps, you have to use two of them per side and stagger the screws 180*. And you have to be careful to NOT overtighten them, because they will bunch the hose up, and create an airspace under the screw-box. You probably won't see it, but the pump will love it, on account of sucking air is easier than sucking gas.
Now; you can prove that the pump is sucking air by doing a fuel volume test. Just run the pressure side into a clear glass 2qt pickle jar or equivalent, with the line submerged in the fuel. Then start the car and let it idle on the gas that is in the carb. If you see bubbles, there you have it.
While yur doing this, your pump should supply about 1qt in a minute or less at 500rpm.
If the pump still bubbles after you replace the rear jumper, and the fuel line does not have a leak anywhere; Then;
your fuel-line may be severely restricted . When fuel under suction has to pass thru a restriction, this action often produces bubbles. What I have found in the past is that water collects in the lowest point of your fuel line, and rusts the line from the inside out. The rust forms a restriction and a resulting soft-spot. My trusty pliers finds that spot for me in short order. Then I just cut it out and fix it or replace the whole line.