Ill post this here in case anyone does a search.
In mid 2008 Savage change the specifications of their rimfire receivers(both MKII & 93R17) to what is now referred to as an "E" receiver. The older Non-E receiver measures 7 1/4" from front to back and the new "E" version receiver measures 7 3/4" from front to back.
All of the Savage 93, 93R17 and Mark II "E" receiver stocks have the same inletting and are interchangeable. The only difference is the metal plate around the magazine opening and barrel channel.
Savage 93, 93R and Mark II produced before the "E" receiver will require some fitting at the safety and barrel channel to work in the "E" receiver stocks.
The "letters" after the model refers to the factory stock and barrel style:
Mark II "F" = synthetic stock, tapered barrel Mark II "BTV" = thumbhole stock, heavy barrel 93 BRJ = wood stock, fluted barrel and so on.
Just for reference, the base model numbers are:
93 = 22WMR(Winchester Magnum Rifle) 93R(17) = 17 HMR(Hornandy Magnum Rifle) Mark II = 22LR(and 17 Mach II)