In photo:
Black rod in RH rear extends through floorboard and seats in matching socket in pedal. Flat bellcrank lever attached to black rod extends up firewall behind LH valve cover. Bracket with two holes bolts to firewall. Long rod extends forward from bellcrank to attach to LH side of carb. If I can make ASCII art work...
Code:
Carb
------------ F
\ I
_\__ R
|_\_| E
\ W
\__A__ \
L \ Pedal
L \
I can get a picture of the bellcrank, bracket, and bellcrank to pedal rod but I removed the carb and long rod years ago to connect to the efi throttle bodies. What Orrie and Ogre have posted is different and doesn't have the short rod from bellcrank to pedal. Maybe those units are from six cylinder trucks? I seem to remember the bellcrank is different on the V8 truck so maybe that rod isn't used, either. Or maybe it's a four eyes thing and the 55-57 trucks were different.