it's not that hard...once you disconnect the fuel lines, you can leave the throtle body and PCV hoses connected, just follow the hoses from behind the intake, towards the driver's side until you find the first joint you can reach and pop it off there...it save time of trying to disonnect and reconnect it on the intake in the car....just my humble opinion. took my intake off in 10 minutes (with air) when i did my gaskets...
swapping the parts once the intake is off is easy and straightforward.
when you take the coolant lines under the intake off, be careful not to lose the 4 little (gaskets?) that sit under the ends that screw down...they either stay on the ends or the heads, so make sure you find them before continuing...
did you get the new coolant lines as well? the ones that run under the LS1 intake do not fit under the LS6..
ok, that's enough rambling from me, hope it was some help...
