I wasn't going to responded to this, but since you double posted it.........I will now.
To take a 25 horse implement, and to set it to slip with 'signifigant bog' on a 50 horsepower tractor........is just asking to tear the implement completely to pieces.
Taking that advice will have pieces scattered over a 100 square yard area at the very minimum and should never, ever be attempted by anyone.
Get the factory manual and set it to factory specs. But don't ever set a 25 horse implement, to operate in this manner on a 50 horse tractor.
EDIT: The best advice to give, is ..........set to factory specs...........and if it slips during operation..........slow down, and/or don't till as deep. And if satisfactory performance can't be achieved, buy a properly sized tiller for the tractor.