I have attached the parts arrangement for the throttle linkage on my B20E. It looks like the throttle pedal part (parts #1 right up to #21) appear to be identical for the carb and D jet cars.
It is parts #22 - 30 that attach to the firewall that are D jet specific. Note that the diagram is misleading. Based upon the orientation of the gas pedal, the diagram implies that the bracket and linkage are mounted on the inside of the firewall. #26 and #21 need to be rotated 180 deg around the vertical axis to be in their correct orientation. If you are interested, I might have a photo from disassembly of my car showing the linkage on the firewall.
The throttle cable has a clevis on both ends
https://vp-autoparts.com/en/artiklar...40-b20e-f.html
That clip you show is 677218 and it definitely secures the throttle cable clevis at the throttle body mechanism. I believe that it is the same clip that secures the cable clevis at the crank mechanism on the firewall; but, it has been so long since I intentionally 'looked' at it I can't be sure. The parts diagram implies that the cable is retained at the firewall by magic.
If you can scrounge parts #22 and #26 that would likely be the quick path to dealing with your throttle linkage