#2
I think it's just the way that it's mixed in. it's mixed to sound as if the drums are far away.
Guitars:
PRS Custom 24
Gibson Les Paul 60's Tribute
85' MIJ Strat
97' Snakepit Les Paul
LP Traditional 1960 Zebra
MIJ Tele
MIA Strat

Amps:
Silver Jubilee 2525
Peavey Ultra 112
Jet City JCA50H
66' Bassman
Pink Paisley Princeton RV
74' Vibro Champ
#4
Some sort of guitar amp simulator can produce a very similar sound if you work it right.
#5
There's a boost around 1kHz, cuts around 3kHz and the low end area, say 300Hz, to add a boxy flavour. The cut at 3k brings them back in the mix.

There's also a large reverb which, along with almost all of the natural ambience, has then been gated.

There's almost definitely compression on those tracks, but it's not what causes the effect.