You should be all set. No mount sticking up to mod, no worries of fans, no issues beyond swapping the dipstick tube.
One bit of advice is to take a close look at where they put the O2 bung. I have seen some that hit the body of the W-body cars and would do the same here. However a buddy that bought and installed them last week mentioned the bung was in a different location.
Buy Torca clamps for the front to crossover and crossover to rear, and it would be nice to have a couple underneath as well, but that depends on how you decide to connect.
00 Regal GS: All kinds of cool stuff.