Purchased the base mounts for a model 70 post 64 express rifle but rear sight screw spacing did not align. Had to purchase 50069 for model 70 long action. Luckily I have another rifle to install on. Leupold has specs for all items, except screw spacing of scope bases, had to contact leupold directly.
Pros: Easy to install, maintains manufacturers specs
Cons: Manufacturer application data mis-leading
This review was written in the old system and had content requirements that are different than reviews written today.