Typically its going to be 1/4″ per click at 100 yards. so if you took the 8 inches x 4 its 32 clicks. Since the angular adjustment is greater at 50 yards than it is at 100 yards it should be double the 100 yard adjustment so should be 64 clicks to cover the 8 inches. The other way to look at it would be the amount you are off at 50 yards would be double that at 100 yards. So if you’re 8″ off at 50 you’d be 16″ off at 100. so I think it should be 16×4= 64 clicks to cover the 8″ spread.
In my experience if you just pull the bolt out (if 30-06 a bolt action) and visually bore sight it, meaning look down the bore and see where its pointing on your target, then adjust the scope so that it is aiming at that same spot you should be pretty darn close at that distance.
If youre having to dial a lot just to bore sight it the mount is likely off and youre not going to be able to dial much for distance if you need to in the future.