I bounced back and forth between a beefed 901 trans and a 915 trans for my 3.6 conversion. What finally settled my mind was the thought of all the work to build an awesome 3.6 car and then having to baby it to preserve the tranny. I finally decided to go with a 915 with wevo goodies. It's a considerable expense, but hopefully worth it in the long run.
My 901 mind was thinking....hey they're cheap and plentiful enough to have a spare sitting on the shelf waiting for when I spit the gears all over the road.
My 915 mind cringed at the thought of some ape hooking a chain to my carerra a-arms to drag my locked up 901 trannied car up the back of a flatbed truck, whilst ripping off my air dam and maybe a bumper.
You need to decide before buying a flywheel and clutch goodies cause once you commit to these parts you can't change your mind without flushing these parts.
There should be some pics posted shortly outlining a 915 being prepped for use behind a 3.6 (mine
).
Good luck with your project!