ThanksThey make an aftermarket fuel pressure regulator you can use to lower the pressure to carb levels. I've never used one and don't know much about it, but I do know a lot of guys use them. Another thing you can do is weld a "sump" pan into the bottom of the tank and use an external electric pump. You can run new braided fuel lines all the way from the tank to the pump (with or without a return line). If you don't like the idea of welding a sump pan with fittings into the tank, you might be able to use bulkhead fittings. Just drill holes and install them. You can either run all new braided fuel lines all the way up to the carb or you can simply cut the factory fuel lines and use short pieces of rubber fuel lines with band clamps to plumb in the external pump and filter.
On my pace car, I did the sump pan and all new braided lines. Pump and filter are mounted back near the tank. I mounted an adjustable fuel pressure regulator on the passenger shock tower and more braided line to the carb. The whole setup with lines, fittings, etc was around $400 (maybe a little more). Not the cheapest route, but not terribly expensive, if you shop around for the right parts.