If you change the bell housing it will still remain the same length. The bellhousing is literally the same except in some cases the ribbing is more extensive and the front countershaft bearing is larger (should be 62mm.) The shortest FS5W71C transmissions are in the D21 if I remember correctly. The "C" trans is a marked improvement in reliability over the "B" trans, though many inner components appear the same. In basic "C" form you get a double cone syncronizer on 2nd gear, wider gears and a stronger input to countershaft setup, as well as an improved shift mechanism. These are big changes that make this transmission much better.

Ok I picked up a 71c box from a d21 navara. Was cheap and seems ok to me. Not any noises really and not much play in the input shaft.I thought was from a z24 but was from a ka24 bolt pattern is identical add la for the bell housing

Any way I know,stumpys are 660mm this one is 700mm.

If I swap the bell housings will that shorten it 20_40mm? Unlikely and if ut did wouldn't the input shaft still be too,long?

Seems like a good upgrade over the 71b stumpys especially with the improved shifter mechanising like s13 boxes.

Any one used one if these boxes? Ratios also seen a bit better than a 71b for my intended purpose