Tricky one this one. I read somewhere that Billy Graham himself said that they never had a contract and it has always been a gentlemans agreement.

Therefore what does he get 10% of?

10% after Ricky has paid everybody else?
10% of Ricky's inital bout fee
10% of any fees plus PPV revenue
10% less cost of accomodation and travel

Without a contract its all up in the air for me, unless it is all in his book.

May depend what the 10% has been previously.