Beveling of the Redfield rear sight base, also called the "Cloward style", needed to be done for the early issue L&S Ultra 30mm ringsets. The nuts were machined with a shallow depth collar section that caused the tightening flats to gouge the top of the Redfield. Later issue rings had deeper collars that gave proper clearance. Some snipers simply reversed the rings with nuts mounted on the right hand side to avoid interference.
It's also been noted that L&S did not machine the early scope mount base, instead subcontacting Brookfield Precision Co. to produce the Long Action Ultra scope base for the M24. This is documented in early L&S catalogues which did not list an LA700 Ultra base. I've heard that the Brookfield base was a slightly narrower width to conform with then current Weaver dimensions. That caused the ring base clamping part to move further inboard, which made the nut contact the Redfield mount. After Brookfield shut down, Leupold approached Badger Ordnance to make the scope base.
Depending on what rings you use, beveling might not be necessary.
I'll edit this post with a pic of an issued WB-490 Redfield thats been modified.