Instructions for stripping JKD five speed gearbox to change final drive
Remove black bung in speedo housing
Remove bung and large circlip using circlip pliers
Tap (not drift out the layshaft) gently
Lift out the fifth gear laygear taking care not to drop the thrust bearing assembly (4 pieces including spacer. Remove bolts from speedo housing and remove in conventional way.
Unbolt 5th/reverse selector fork after undoing lock nut holding allen screw.
Lock up gearbox as per 4 speed see Haynes manual and undo 1 5/16” bolt (LEFT HAND THREAD). Remove the centre from the hub and make sure layshaft spacer is turned so flat part faces fork side. Make sure that you watch the syncro hubs so that they are fully engaged and don’t go over centre – otherwise you’ll be stripping the box completely to reassemble them!
Slide out inner race from reverse gear. Note reverse has a machined face on syncro hub and baulk ring is a loose fit and is only there as a spacer.
Ready to fit pinion. Re-assembly is reverse of dismantling. Make sure that 1st motion shaft gear and pinion are torqued to 150lb/ft. You’ll need a friend to stand on gearbox when you do it – good luck!
A couple of other pictures to help you !