Thanks so much for your help.Obvious observations to me:
-sloping top tube
This makes the frame a 1990 or younger but also not an Epic.
-affixed seat post clamp with the center area indented around the circumference
This excludes M2 frames or composite frames where the seatpost clamp is milled; i.e. your bike is steel frame (do the magnet test to confirm). The actual bolt going through the seat post clamp is also not original.
-lack of eyelettes
The only non-eyelette chromoly frame they made in the early 90's were the 1992 and 1993 S-Works Stumpjumper steel frame.
-components
I suspect the thumbies are original. Check the date codes on the thumbies.
-rear dropouts
The triangle hole makes the frame chromoly. M2 frames have solid dropouts.
-rear cantilever cable stop arch
Your frame doesn't have one, unless that too was ground off with the (maybe) eyelettes. The arch went missing in 1993 and some people claim a missing arch on their 1992's. Catalog pictures have the arch, but tons of photos of 1993 Stumpjumpers do not. Rather, the frames got a metal noodle welded onto the non-drive side just below the seat post clamp. The only other frames that did not have the arch were also the 1992 and 1993 S-Works.
The serial number should have an S or K in the third digit to be an S-works.
Ultimately, I am stabbing in the dark. So take this summary worth a grain of salt.
Frame is definitely made of steel. Third digit in serial is an "L". (see attached pics).
I used acetone to wipe paint from the dropout, no evidence of grinding anywhere. Original paint was white.
Frame does not have a cable noodle for rear brakes, no evidence of being ground off either.
I believe this bike originally came with the white Judy fork currently installed as it is a 1" steerer and evidence of white paint under that crappy
blue make-over.
Wheels are BX23 and hubs are Deore XT FH-M732 / HB-m730.