It's more than just the primary cover. According to the Snidal manual it has "..cast-in "tunnels" in crankcase and primary case castings."If it was simply a case of a hole in the primary cover I could swap the 4 speed cover for the 5 speed one. That's what I thought I would be able to do when I bought the transmission.
From what I have heard to do the swap and retain the left shift you'll need a set of motor cases along with the whole primary drive side...CJ
(spellchec didn't even pickup on the "bassackwards"... WTF??)