Changing from early gearboxes to later, how do you go about the speedo drive?
 

When going from the early gearboxes ie TY752 to a TY754, how do you go about the speedo drive as early boxes are cable driven and later boxes are electronic?
Cheers.

Quite simple mate,both output drives on the boxes are identical so just pull out the electronic sender unit in the new box[threaded so unscrew] and just wind your cable drive in but be careful to get the t-piece that's at the base of the cable located properly in the box when you install it.

As above.
I have a 754 box in my preface classic, and its a straight swap, apart from Linkages (you`ll need a facelift gear lever), and you`ll need to tap a thread into one of the starter holes, no biggie. Just remember to swap the rear diffs at the same time so a matching set goes in, saves any undue hassle later. Even if they are the same its worth changing mainly cos its newer, and you`ll have a spare.

Thanks Scoobynet people! Very helpfull once again!