The only manuals are for elarier generation cars, up to approximately the mid 70s (I think the MSCC still list them on their web site). There was also one by Autobooks, but again for the earlier cars.
As suggested above, engine manual from one group, gearbox from another.
As well as Morganatica there is also GoMog (which hopefully now it's been revamped a bit has removed some odd inaccuracies...).
Welcome to Morgan ownership and this forum.
Cheers,
