Classic/Antique Car Repair: 66 Mustang stalling/chugging, rust deposits, rusty tank

Question
Our '66 289 4bbl (Edelbrock Performer) has recently suddenly started chugging and stalling at all speeds, most recently on the freeway (fun).  If you get it started again, it will run very poorly, as if it's starving for fuel - hence a new fuel pump, but to no avail.  Once running, if you rev it up a bit, it will "pop" into running great again.  Today it died again on me again, and will turn over but NOT run.  The previous owners had 2 fuel filters on it (now it has one) because of rust deposits in the fuel tank.  This issue happens no matter how much fuel is in the tank.  We're thinking of 1) carb issue or 2) rusty tank/filter issue. Any ideas?

Answer
My guess is that there is a lot of crud coming through with the gas, and your carburetor is probably contaminated with the stuff.   I avoid trying to dope out what happens when a vehicle has non- stock parts on it, but if it were mine, I'd take the top off the carburetor and just look into the float bowls - if there is dirt and grit in there, you've got a seriously contaminated fuel system. Step one is to get the tank cleaned out at a professional tank-renew service, then replace all the fuel lines, all the filters, and have the carburetor cleaned out and checked for any other problems it might have.

Dick