I swapped my 4 banger motor and transmission for a 1940 V8 with transmission . I thought King shift made repop shifter linkage for the side shift 40' transmission to convert to top shift I've done a search but can't fine anything . I've never consider until now but i was toying with the thought ....
Why not use a '39 topshift trans(or a '40-'48 pickup topshift trans)? would be a bolt-in(just exchange tailshafts/housings between your '40 & the open drive Pu trans). No "Mickey Mouse" linkage, just all stock parts.
If the transmission you have is a correct 1940 sideloader, it’ll have the preferred late style gearset. Your best bet would be to get a 1939 gearbox and shifter housing, and swap the ‘40 gearset in, as suggested above. The shifter housing must have the correct 1939 second/high shifter fork. There were Hurst shifter conversion kits made years ago for the 1940 side shift transmissions but they aren’t made anymore unless the new Hurst has just brought them back. Somebody made have an old original Hurst kit for sale. There are some current production shifter mfrs who may have this conversion kit but I haven’t heard anything good about the quality.
I presume it a small early hot rod, so to give your self the most foot room ,do as mac VP said swap the 40 gears into an earlier top shift case.
If I'm not mistaken, a 37 or 38 case can be used in place of the '39 case if you can't find one, and also F-1 truck shifters up to '52 can be used in place of the '39 shifter too, if you have to piece one together. You've got the good guts, now you just need the case and shifter to put them into, and everything else should bolt up.
Yep I’m going to start the hunt for a 48 or 78 case . Towers another story . Van Pelt was very helpful on my last AV8 build .
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