I know I'm topping old ****, but this is ****ing hilarious. Holy hell GOLD.
As for turf mode, I've rebuilt several for this thing grenading. Not a fan, but if you don't put big tires on or bounce the rear, its fine. Think of it like a D30 with a lunchbox locker on 35's. Don't let it leave the ground or land under any amount of throttle. Ever.
You can drop the spool out of any 570/900/1k in it except highlifter (I think that's where they geared different). The HL reverse setup still works. You can use the gears that create overall gear ratio out of about any of them as well. I have 570 gears in one trans on the shelf, my buddy had diesel ranger gears in his XPT drag racer for a while trying to hit 150mph. laughing1 but seriously.