Gearbox and engine compatibility

[peteoddcar]

Hi all,
Long time since I posted but I am finally getting round to re engine and add overdrive our Dolly.
So here is what it is currently
TR7 2L engine with parts swapped from the original 1850 ( by the previous owner so not quite sure what had to be changed )
Non overdrive Ex Vitesse box with 1850 bell and clutch
Sprint axle
Modified ( shortened ) 1850 prop shaft.

Ok so far ?

It’s worked well for about 12 years

What I want to know is can I bolt a Sprint o/d box onto my 1850 back plate.
If so what flywheel and clutch do I need.?

I have a sprint overdrive box and prop with all mounts etc from the donor car.

I also have a late 1850 box and overdrive with all mounts etc. So I think I may need to mospd the prop again?

Any suggestions welcome

[peteoddcar]

I forgot to mention I have another good TR7 2L which is going into the car as the old one is knocking and smoking a bit