The Vortex GE will not take you very much passed 1,000 yards. It has barely half the moa elevation compared to Tactical LR scopes.
The Vortex GE is excellent for up to 1,000 yard F-class and 1k br. With the GE to get to 1,000 yards with your 308win you'll need about 30 to 35 moa of adjustment. GE has about 55moa total elevation. Half of the 55moa will be usable, so with a 20moa base you'll have a total of around 37moa elevation. So you'll want at least a 30moa base to comfortably reach 1k with your 308win.
You can use the XTR signature rings (excellent rings and very recommended), with them you can get 40 moa extra elevation.
The 308 Winchester cartridge is ok for up to 1k, maybe 1,250 yards with the right loads and in the right environment, but there are much better choices for LR shooting.
On the bright side, you'll get excellent barrel life from your 308win and if you don't handload there is plenty of good factory match ammo.
Get yourself the APA little bastard brake and don't look back.