Thanks for pictures. First one shows the area of my interest.... With the grease, hard to see how the 2 parts are connected in middle, if at all, but shows the bushings at top and bottom of the "box", that I suspect are loose on mine. Would think: Got to be some type of support beyond just the top and bottom bushes.. for output arms... Housing may be worn out.
While I had the column (top end) apart, I tightened up the fits on the top shifter to rod (hole was still round, but pin/bolt was worn), and made/added a flat rubber washer on ball to make it less "floppy" (put under the round "nut" that holds shifter on column and outside of ball)....thought perhaps it was dropping out of gear from sheer gravity, acting on the heavy shifter handle when in 2nd...can't say that was issue or not, but is tighter than it was...
If you take either of the two output arms (flat bars) on mine and "wiggle" there is what I'd consider excessive slop. Appears that the bushes in first picture are worn, perhaps in the housing. Car shifts, sort of Ok, but has been dropping out of 2nd at light load/coast, and got it stuck in 3rd for first time the other day (speed shift, hard......came out at home with help wiggling shifter while I did same at control box...noted excessive play....BoatingBill may have me pegged, or my arms need peening/pegging?). My experience with other gearboxes, is these faults are indicative of internal issues, like worn synchro, and excessive axial clearances in stack up on 3rd motion shaft. (Don't want to accept a teardown just to look, and for now is driveable.....so holding off on that.)
You asked about the rods and adjustments. All I can contribute is what my manual said... Put in neutral, loosen the jam nuts, and put the factory "gauge" on (hole in top), then adjust nuts to match. I'd say the intent, is to get the two halfs "even", or flat, on top of joints in the box, not the outside arms, when in neutral, then with change rods in middle of travels in box, match them up to the control box's neutral... can't say if both output arms would "look" level on outside, perhaps so, but issue is to get the "timing" set off the middle point of travel inside the control box. Others, may have more to add.
So, .......
Maybe not much help on your issues, but would like to know even more about what's going on inside the control box on mine... and if tightening up the action between the two arms is worth chasing...
Again, Thanks for the photo... don't see anything that will come bounding out so, may open it up now it's been filled up with more grease..... geeze I hate getting that stuff all over...!
Bob L.