Tony, it's very much based on mulit-tracking ala Les Paul. Also I'm not tied by recreating a known tune. Believe it or not, It's far easier to work on original stuff as you can then meander to your heart's content. The real difficulty is knowing when to stop and not to over-egg the production.
One guy on You tube illustrates the freedom of 'new unscored music'
Like me, he has a Line 6 DL4 ECHO modeler which has a good loop facility. He builds up the sounds one on top of the other as you can see in the clip. That's OK but if you make a mistake on one take then the lot is ruined. Andy is producing his sound from pedals--The beauty of PC multi-tracking is that you can re-create everything Andy is doing via VST efx.
I've moved on from that concept by laying each track into a PC multitracker (Sony Acid) on which I assign various textures and efx to each track. That way I don''t waste hours of time. You do need to have a feel for how the track is developing and I have loads of takes as 'saved as' then I spend days listening to how it all sits together before it's released.
I do urge anyone to use your guitar as a sound making tool, one to be experimented with in all the ways you can find possible. This ambient style is not to evereyone's taste but I use it to illustrate how versatile the guitar as an instrument is. Here's Andy Othling as Lower Case Noises using the DL4 & the peedal board you see on You Tube
Not exactly Shad related but it involves a guitar
Bri
ps, My DL4's for sale--not used it since I moved over to VST
http://line6.com/dl4/