Transaxle for an Audi 2.7 Biturbo

I'm fitting a 2.7 bi-turbo to my Porsche Boxster S. I'm trying to work out the best transaxle to use. It all gets a bit confusing and I don't want to be randomly buying gearboxes to test things out.

I wanted to use the standard G86.20 trans which i've read is basically an Audi 0A2, the bell housing is slightly different for the Audi 2.7 engine (starter motor is in the wrong location). I was going to cut and weld it to overcome this but I've just realised it doesn't have the provisions for the speed sensor on the driveshaft flange or the hole for the engine speed sensor on the flywheel.

I believe an Audi 0A2 will bolt straight up and has the same sensors as used on the 2.7 bi-turbo. Where I get confused is there are lots of different variations of these transaxles. Another option is the 01E.

I wanted to use the Boxster S trans for the obvious reasons of not having to fabricate mounts, driveshafts or the selectors.

I'm wondering if one solution could be to build a hybrid box using the Boxster S box with an Audi 0A2 bellhousing. Is this even possible? I found a workshop manual for the 0A2 in German but the pictures suggest not. That being said, i've had the bell housings off a few Toyota transmissions where the method for doing so isn't covered in the workshop manual. Has anyone tried removing a bellhousing before?

Another option is to go with the Boxster 5 speed gearbox (G86.01), I know this will bolt up (requiring a lot of hardware changes or changing my Boxster S for a 2.5/2.7 car) and has the sensor provisions I need. It'd basically be a bolt in solution (so makes sense). I don't think it'll take the power i'm planning 400-500bhp plus i'd like to keep it 6 speed.

Is anyone else using this engine, if so, what trans are you running?