* use heavy strings and tune down to open Eb instead of E (makes it easier to play, and keeps harp players from sitting in uninvited)
* only use the neck pickup on your strat, experiment with pickups that are hotter than stock
* if you use a tubescreamer, use a ts-808 or a newer one modded to that spec and keep the tone backed off, srv was not trebly
* strengthen your hands. srv used a lot of hand/finger strength
* if you can afford it, get a dumble amp :-) (or a two rock or a fuchs...)
* try 15" speakers. srv used some fender amps with 15s instead of 12s.
* watch srv video. there's a bunch available.