Happened to email Mudd's Customs today to see if their 120R handle would fit a 120R MSL (Mechanical Self Leveling) loader. With their permission the exchange is posted below 
Do your loader grab handles fit onto the 120R MSL (Mechanical Self Leveling) loader?
We just finished the new design and will have them powder coated next week for the new MSL.
Mudd's Customs LLC