Tranmissions and conversions help Adapter plate

[Frankenstein71]

So I am building a VW bus with 33 inch tires.

Yes technically wrong forum but I ran into a complication as I wanted high HP tranmission. 350 or 400hp.
I have a ford 2.3L svo turbo motor. (Old mustang motor)
VW Bus transmission cant handle this without hardening the gears and that will prevent high milage. Want to travel around camping.

The adapter plates for my motor are 915, 930, g50 tranmissions.

The 915 can not handle the HP.
The 930 and the g50 are expensive
I found a good priced 930 but it does not have the lsd installed and gearing is off.

Which got me thinking about a 928 tranmission. can it bolt up to a 930 adapter plate?
or a 951 tranmission can that bolt up to the g50 adapter plate? I believe that was the audi model.

And can they handle the HP and size of my tires.

Could I use a 925 tranmission? I heard automatic and had a tall firt gear on the 3 speed.

Any help would be appreciated. I know its not a porsche I'm working on. But Have to respect the brand. Porsche does make great stuff.