This is purely hearsay from me as I have not made the conversion you are asking about.
The '72 probably has the rounded tunnel in the floor where the later cars with rod change had the more squared off tunnel. To fit the rod change to the '72 you will need the rear hanger bracket adapter kit. I know Mini Mania has sells this, I don't know who in the U.K. does. (MM part number 22G2026MM).
The remote shift originally in the '72 would have used the shift housing as part of the engine steady setup. When fitting the rod change you will need to fit additional engine steadies to handle this.
Ok, thanks. Yes, will be fitting an extra upper and lower engine steady so this will not be an issue.
Why not fit a remote change box? Gives much, much better engine stability than a rod change and, some would say, a better gearchange.
I have driven a couple of Minis with remote change boxes and to be honest absolutely hate it. Also the engine I have has the casing for a rod-change.
I do have the floor pan piece from a later car, so may look into cutting out the old and welding in a new piece. I would like to avoid this, so am looking for any kit or conversion method there is.
Surely someone must have done this before?
Thanks for the everyone