made my custom shift linkage....

Looking at the first pics you posted, it looks like all you would need is to install the 1-2 shift rod on the transmission side of it's lever.
Using the shortest transmission shift arms available to you will give the tightest shift pattern with any given shifter frame.
Super Shifters use straight heat treated and sleeve reinforced rods for the forward gears and it looks like they'll work here too. If you build your own to work with the rod ends, after the shifter frame is bolted down solid where it's going to live and everything is neutral aligned, make sure they're long enough to cover all but a couple of threads on the rod ends and trunions.


You summed up very nicely what I was trying to say with my convoluted ***. Thanks. lol