Your bell crank is the issue. I had the same issue where the linkage was getting hung up and going to the stock setup or buying the setup mother trucker is talking will solve your issue as attested to by latroca52.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum