Can a 400 series short output shaft be exchanged for the output shaft in a 425 series trans ? I am aware that an adapter will be needed to mate the housing and a place for the fill tube will need to be fabed. Plans are to use the trans for a mid-engined car but I need to move the weight forward as if left as is there will be too much weight behind the center line of the axle. Any info from those more knowledgeable would be appreciated

 

Other folks have turned the Toro drivetrain around (engine facing rearward) then split the differential from the trans case. You can move the engine/trans assembly forward then build an adapter and driveshaft to go between the trans output shaft and the differential case. Of course, you'll need to flip the differential so the car runs in the right direction.