Got a 468, Carter AFB, and a Holley 130gph mech pump. The pump has two lines, one from the tank, one to the carb. Is it ok to run it without a return? I don't have a regulator or a pressure gauge, so I have no idea how much pressure the carb is getting. Would it be better to run a return line? If so, what is the best method of running one? Any thoughts or experiences with this would be very helpful. Thanks!

That pump puts out 7-9 psi.

That's WAY too much for a carter or edelbrock carb. Any more than 5.5 psi and you start getting probs from it.

I limit mine to 5.25 psi.

put a regulator on it ASAP!

I really wouldnt worry about a return setup right now.. You get more major things to deal with right now (psi going to carb)

You can run a return style regulator and kill 2 birds with one stone. If your using the stock '73 tank with the stock pickup assembly it should have a tube in it for a return line. Just run a line from the regulator to the tube and your set.

What will that extra 1.5-3.5 psi do? I've been running this setup now for quite a while without any problems.

It will over power the floats and dump raw gas in the engine. If you've been running it like that with no problem I think your not getting full pressure due to some sort of restriction