Pavel, I smell what you're stepping in: I agree that we have to "leave only our tracks", but don't forget that emissions regulations were instituted because the volume of "tracks" was too big for mother nature to deal with.
Where I'm at, these tracks that I (along with the rest of the motor vehicles in this country) leave due to a lack of cats is not enough to challenge the CO2 cycle.
As far as that delicate engineering you mention, I agree that our vehicles are a clever balance, and that rov'n should be careful with some of the mods he's thinking of. Nonetheless, given my recent reading (and the fact that there are a whole bunch of Discos out there with no cats), legal, moral, environmental considerations aside, I'm sure the modification can be done.
I'm glad beerdrinking isn't this controversial...
Cheers!
___________
MG
'95 Disco, 3.9L
Discoverying Bolivia...