I just put all the gearing from a 46 Ford side shifter into a 78-7006 floorshift case. I installed a 68-7222 top cover, which drives the synco too far toward the input shaft. Any ideas on a modification or alternative shifter fork which will correctly locate the syncro?
You need to find either a fork with an 81 prefix, or a top cover with a screw head on each side of it (double detent).
You need the 91A Fork, which is a hair less than 3" across inside and almost always has the 91A PN forged on right above the fork. The fork has become very difficult to find as a part, and you will most likely find yourself buying a complete 81A top ***embly to get one. This fork was used on those '39's that had late style synchro and all '40-52 pickups using this trans. Top has the big screw plugs over detent hole, but was also used '38-39 with small fork like you already have. If you do use a 91A fork to convert, I'd say check travel of the fork as well as initial location carefully--I'm nearly certain the travel for 2-3 fork will be the same as you need, but cannot say for sure since I've never used a '36-38 top myself. I am currently getting a 68 type shifter freed up for a HAMBer who needs it, and I will check its travel against a late setup once the blasted thing moves freely.
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