MackRack:

Since I don't know what bases you have I will give you a list of ring sizes according to two base information:

For Win. Model 70 (Long Action) Fits post war non-Express models (serial # higher than 66,360)

STD 70 RVR (2-piece): Low
STD 70 RVF/R (2-piece): Low
DD 70 (2-piece): Low
DD 70 RVF (2-piece): Low
QR 70 (2-piece): Low
QRW/PRW 70 (2-piece): Low
Mark 4 70 (2-piece): Med

I have the exact Conquest scope, and I measured the objective housing at 1.81", and the Leupold VX-III 3.5-10x40's objective housing is 1.8" (the above information corresponds to the Leupold VX-III 3.5-10x40). The Conquest scope is .39" longer which I don't think will make a difference if it was shorter than the Leupold scope it may make a difference.

Good luck.