I had the same issue ...& the overpriced lokar stuff also looked really out of place.
I used the interior linkage off the pedal from a 65 Impala, then connected a Lokar cable to have a pull throttle. Had to attach a bracket to the engine and also had to weld some tabs onto the linkage to properly (the correct angle) through bolt it to the firewall from the inside. Still have to do some cosmetics on the opening. Similar interior linkage is available from sites selling early Camaro repop stuff.
You can see some of it in this pic
Gas Pedal