I hate to beat the dead horse ... but if that's the sound you're really going for you should spend your time amp shopping. (With an Axis in hand, of course.)
Go to one of the other forums and listen to clips of the Plexi clones/derivatives- the Variplex for example or the Metroamp 12000 series, etc (go to the Metroamp forum and listen to "rockstah's" clips). Plenty of guys who have nailed that tone with the right amp. For a modern take on it, the new 5150 channel 2 gets in the ballpark.
Sure the guitar, pickups and fingers play a big role but the characteristic attack and tone you're looking for is in the amp.