There is two completely styles of kickdown linkage: The 3-piece setup and 1-piece setup.
The 1-piece setup will rarely fit (and work correctly) on an FMJ - for it hits the firewall. I have seen one car use it OK and I know of a friend who said it worked OK for him (but I didn’t verify it).
The 3-piece setup will have two bell cranks on it. One at rear of intake manifold and other on transmission bell housing.
Only the lower bell crank and horizontal rod will work between a 2-bbl and 4-bbl versions.
The top rod and vertical rods are different, as well as the top bell crank and mounting bracket.
NOW with that all said, there are several versions of small block linkage out there – for Chrysler liked to change things up every couple of years or so – so it is always best to get a complete set from a working 4-bbl small block.
The 3-piece setup came on all FMJ’s, all A-bodies and older (not sure of changeover but ‘72ish, or so) everything.
After ‘72ish (or so) everything else, including pickups and vans) went to a 1-piece setup (it was cheaper to manufacture).
Sometime in the early ‘90’s, Chrysler finally changed over to cable systems.
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One thing to keep in mind is a majority of 4-bbls out there use the GM style linkage (on carburetor). The at-idle position (throttle stud) is roughly at a 10:30 O’clock position and WOT (Wide Open Throttle) throttle stud position is at roughly 1:30 position.
Chrysler does it different and the at-idle throttle stud position is roughly at 11:30 position and WOT position is at roughly 2:30 o’clock position. This doesn’t sound that far off – but will make your kickdown linkage act wacky - and also leaves your throttle cable “too short”. Too short leans if you give it gas enough to allow engine to rock in place, the throttle cable will pull backwards at the adjustment pinch bolt. What that does is will hold your throttle open – which can make for a bad day – real quick (if you were driving at the time).
4-bbl FMJ cars have a longer throttle cable – which is still being made new from Pioneer (most likely from your normal auto parts store). Others might still make it, as well.
Your carburetor manufacture should make a "Chrysler" or "Mopar" adaptor that will bolt onto your carburetor to fix the clocking issue.
One last thing, the throttle cable attachment (throttle stud and cable adjustment pinch bolt) do sit a bit over-center over of the top of drivers side valve cover - on 4-bbl's.
The 2-bbl versions (throttle stud ad cable adjustment pinch bolt) is all not even close to being on top of
Left valve cover (when looking downward).
BudW