Jerry,

I may have misunderstood what you are describing. It's normal to have to use choke to start the car and keep it running from a cold start, and 5 minutes is not an unusual amount of time before it will idle without any choke at all.

You should not need to use the gas pedal to keep it idling, however. Take a look at how the choke cables are adjusted -- with the choke pulled fully out, the jets on both carbs should be pulled down 4-5 mm off their seats, and both equally. The cams on the carbs should be actuating the fast idle screws to hold the throttles open a bit more than with the choke off.

With partial choke, the jets should return to their seats, but there should still be some fast idle function engaged. With the choke fully in, the fast idle screws should not be touching the actuating cams. It takes some tinkering with cables and adjusting the fast idle screws to get all that to happen.