[Naumoff]

Just looked at my linkage and I noticed where your rod attaches to the lever on the driver side is to far forward.
You not having two four carbs changes the connection point on the carb pushing the lever farther forward which might cause a problem. The rod from the pedal to the firewall pivot is also on a pretty extreme angle. Mine is straight. I will take some pictures of my set up and post them when i get a chance.