Several aftermarket suppliers sell a V-8 throttle linkage assembly for TF trucks. It should be adaptable to your series truck with some tweeking.

Martin,
The aftermarket catalogues I have only show the pedal and linkage rods for 60's trucks, not the assembly.

Fred

1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine