I had exactly then same problem, and even with extended bases I could not mount the scope far enough rear ward to fit me, without crawling up the stock when I mounted the rifle.
The V3 Leupold in 3.5x10 has a longer tube than the 2.5x8. So I traded the 2.5 in on the 3.5. Since Epps could not mount the scope to suit me switching scopes was not an issue.
Anyways the 3.5x10 with the extended bases puts the scope exactly where I what it. I have three M-70's, 30-06, 375HH, and a .243. I have a Kimber 8400 in 30-06 and the same issue arose, it has a 3.5x10 with extended Leupold bases as well.
The newer scopes all seem to have shorter tubes, they say it is to reduce weight. But it is a pain in the a$$ to mount them. The old steel Weavers had much longer tubes and were a breeze to mount as there was a lot of room for fore aft adjustment.
There is probably more than one way to skin the cat and perhaps your body dimensions differ from mine. But this is the way I solved the issue.