I have a J100 made by Marshall. Complete with inlet and outlet manifolds, this set up is intended for a nose mounted application where blower drive (available thru several UK suppliers) passes below the radiator.
Blower was restored with new bearings front and rear, new matched gears and new lip seals to prevent oil passing into the rotor cavity.
The rotor shafts should be swapped for gearcase fitment and drive into the lower half.
This is a size up from the J75 often used on prewar J,P, and TABCs. The 100 however has been well adopted for engine sizes around 1000cc, like N, L, K, and is a great fit for Ts.
3400 gbp ono
More pictures on request.