fs5w71b tail housing question

[Datrock]

Hi, I am Roadster owner that has a 5 speed from 720 diesel that I'm installing in a 67.5 spl, the truck was a 81 but I'm not sure if this transmission is that year or not since the engine and tranny were not original to the rig, it has the smaller 56mm front countershaft bearing and an aluminum input cover, and Warner type brass synchro's in all 5 gears instead of a steel servo 5th gear synchro like I have seen in other photos.

My question is about the speedometer cable input on the tailhousing, the one I have has the locking bolt and tab on the bottom of the casing and I am wonder if any of the other 31-1/2 inch long "B" type 5 speeds have the locking bolt for the speedometer input at the top of the hole. This is a cleasance issue due to the large X-frame the roadsters have. If I can't find a different type tailhousing I guess I will have it built up at the top of the hole and tap it out...any leads, information, or help will be very much appreciated... thanks... Bill