On mine (1970 RHD), there was so much slop in the pedal and linkages that a lot of the pedal travel was lost by the time the motion reached the carb.
Worst was where the cross-shaft (through the chassis leg) rotates, just in front of the right-hand front wheel.
The hole was oval, so the shaft was moving backwards and forwards initially, rather than rotating and pulling the accelerator cable to the carb.
Also, the V-shaped bracket under the floor, that coverts the up/down pedal movement to push-pull at the cross-shaft, was very sloppy.
And where all the rods connect to crank-arms the holes were worn, wasting more motion.
VW design was to use bent connecting rods, retained with cross-drilled split-pins, but no bushing. So after nearly 50 years they get tired.
From pedal up to pedal down would only open the throttle half way (single Solex) no matter what I did with the cable.
Butty sells kits for updating all of the linkages, but the pedal-to-v-shaped crank, and v-shaped crank to cross-shaft, you could easily DIY refresh with a couple of oilite bushes, rose-joints and threaded rod. I chose DIY from pedal to cross-shaft, but the cross-shaft kit I got from Butty. His kits are simply lovely.
Either way, I would recommend considering having some adjustable geometry in there, so you can control how much pull you get at the carb linkage when you go from pedal-up to pedal-buried-in-the-carpet.