hello new to mopar slant

Guatemala? Wow! How many miles (km?) Are on that thing.

I have a /6 3-on-the-tree in a 1964. Just over 100,000 miles. There is an adjustment shown in the Factory Service Manuals that may help out. I've done that a couple times but I started to have problems again, just as you describe. If you need new rubber bushings for the shifter rods, I have some. That also helps. Honestly, I don't think Brewers can help much.

You most likely have the baby trans like me, "A903" non-synchro first and reverse gears. Unfortunately, there are no provisions on the case to mount a floor shifter. A shifter mounted to the floor with rods going to the trans introduces another place to flex and bind up. If you can find a newer 1970-1981 all-synchro "A230" to swap in, that's a good way to go. I believe that's the one that had a floor shift standard. (Dusters, Darts, etc)

haha yeah on Guatemala, this car has gone through a lot... I recently got it on a deal, so im figuring out a way to restore it a bit.. maybe in the future a small block with auto trans swap. but for now I want it to just work properly kill all the rusted parts and so on...
odometer reed 45k, judging by the car I wouldnt believe its true, its all rusted. hahaha just did the whole floor, now I gotta get to the trunk and rear fenders rust.
I believe this car sat for a long time out and ruined slowly ruined it.. cool part is that nothing is missing atleast not the most important parts and it runs.
yes its the a903. if you had an image of your columns shifter part would be awesome. on mine I see a lame spring also..... i have been writing and searching for days now and no answer or even a diagram. there's an old guy who used to work on lots of mopars here and he claims he has fixed many of these and he might even have a spare 3 speed column laying around his shop... so ill check that out...