You can run the Q-jet with a manual choke, they used to make a kit to do just that. Mr. Gasket or some other aftermarket venders had them. Hotrod Lincoln will gently give you his thoughts on headers. Depending on how the internals of your engine have been massaged you may be killing horsepower and economy with the headers.

1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy