4 speed slipping out of second gear

When adjusting the linkage can’t seem to get the 1&2 gear linkage out past the reverse linkage ! Any ideas ? Or is it just me.

This in reference to taking the rods out of the shifter? You did say 'out'. This is NOT a reference to moving the shifter levers back and forth and the installed rods interfering with each other, right?

It has been a couple of years since I've had my shifter/levers/rods apart. IIRC, the 1-2 shift rod at the shifter does NOT come out unless the reverse rod is removed. The R shifter lever cannot be moved far enough 'out of the way' (back and forth) when connected to get the 1-2 adjuster out of the shifter.

At least, there is some interference along those lines that require something you are not fussing with to be removed before you can get to what you are working on.

Taking a pic of your shifter setup before you take it apart is a good idea...unless it's wrong to start with, and you may not KNOW that it is wrong. I didn't check the above graphic/pic somewhere else to confirm IT is correct, but it looks right to me. That in itself doesn't mean much.

Refer to the graphic/pic above to ensure your levers and rods are correctly placed on the trans AND the rods are correctly placed in the shifter levers. Make sure the correct lever is in the correct shift fork stud (one lever is bent). There are also specific PN levers required on the shift plate. The PN is stamped on 'em.

An aside somewhat: I had trouble keeping my trans in reverse. It would pop out if I did not hold the inside lever forward. I asked Brewer's about it. Having just spent some money with them, I thought it not UNfair to call them for a 'one free' advice question. They were kind enough to talk to be about the problem. They said, 'Are there any shift stop bolts in the shifter?' 'Yes', the answer. They said, 'Take 'em out.' A couple more questions from me along the line of, 'What about this...that...and the other...?' They said:

'Take 'em out.'

I did. Problem solved.

Another drawing for reference (New Features for 1964 - "A-833" Four-Speed Manual Transmission):

Shifter M20.jpg