Is it a struggle to get going? I have a 3.89 diff on the rear already. Would a OD make any difference to the ratio issue?
The box is marked HC so for a vitesse. Could I use the main shaft with my 3 synchros herald box (The answer will almost certainly be no, just checking).
Failing that could I use the main shaft from a HC box in a spit 4 synchro box prefixed FH.
Vitesse 1st and 2nd gear are a bit tall for a 1300 and hill-starts give the (rather small) clutch a good hiding.
I think I said this earlier but you can use the HC mainshaft in a 1300 MkIV Spit box, so you could source a MkIV 1300 non OD box and convert it with the HC mainshaft using the the OD and adaptor from the Vitesse (Vitesse OD may have a higher running pressure than the Spit one, but doesn't really matter).
Broadly speaking, many of the components are interchangeable between 4 and 6 cylinder boxes - apart from the gears themselves as the ratios are different. There is even some interchangeability between single rail and three rail. Plenty of "gotchas" too!
You cannot use the HC mainshaft with the original 3 synchro Herald box.