"... now, for guitar purposes, 330MRAS is 330 OHMS? 0.47uF previous the 500k 2w pot at the output, what kink of cap should be?"
Guitars tend to drive stages into overload and as it stands I suspect that pre amp will suffer nasty sounding "blocking" distortion. IMO the 0.47 caps need to be reduced by a factor of 20 and the 4k7input grid stopper upped to 47/68k. A 100k grid stopper is also needed between stages.
Dave.