Troy-Bilt 33” walk behind having wheel drive control rod issues

[Maussimo]

So I brought this beast back from the dead and nearly every single part on it has been rusted shut or closed and inoperable, until now. I can drive it, it mows, the blade engage works/releases properly when it’s supposed to. My problem is the left hand grip, the manual calls it a wheel drive control rod…it’s the one that connects to the linkage on the left down at the bottom, not the one that’s connected to the brake. It was an extreme struggle to get the linkage bar connected to the handle, and there’s barely any threaded rod left in the swivel block at the bottom. I cannot squeeze the handle at all to engage/disengage. I know the handle should not be this tight. I have taken all of the cams off of the linkage bar at the bottom where it all connects to and cleared all signs of rust and smothered it in axle grease. Everything moves really well. I cannot for the life of me figure out what’s going on. If anyone needs pics or maybe a video I’d be happy to post one up to YouTube if that helps anyone to help me. Let me know if you have any questions! Thanks in advance!