OK thanks everyone. Can anyone confirm if the tailshafts are different lengths between the B10 and B110?

Didn't know you were talking about a B10. Someone will confirm if a B10 and B110 H145 shaft interchange. If so then the H150 shaft will fit. If not a shortened H150 shaft may be an option.

I'll take a guess and say that the 120y shaft its not going to work in a thou. Would put money on them being shorter that a 1200 or 120y

umm B10 (1000) and B110 (1200) both have H145's, and the same gearbox splines... 1200 has the option of an 3N71B (3 sspeed auto) though... which has different splines to the Manual one...

I have the spacer, not sure if the tailshaft from a 120y will work since i have a B10. Does the B10 and B110 have the same tailshaft?

just make sure it's noit an early 120Y - they have a H145.... The Defect III had one... if it's '74 120Y then it'll have a H145...

and TD3 is a July '74 TD3 now has a Borg warner 68 out of a March '77 120Y, so no more weak diff,,,

you'll need a 2.5mm spacer if you out a H150 crentre in a H145 housing ( I had this planned but the axles would NOT come out so i thought stuff it and went and pulled the BW68 out of my first 120Y...

120y [H150 equipped] tail shaft is what you need.. no mods required.

Running the H145 and 12 inchers has it's upside, nothing breaks but traction.

Do you have a mate who has a lathe? A friend here will shorten and weld a tailshaft for $50.00. They aren't balanced though so balancing costs a bit extra.

So I only have one piece of the puzzle then, and shortening a tailshaft is a bit extreme at the moment. Might have to go back to h145

You need a H150 tail shaft also. I think that would be easiest. I've never tried to swap the flanges over so I can't tell you if it's doable (good idea though).

If you were to use the H150 TShaft you'd then need to get it shortened.