1) LS1 radiator and fans will work fine, chances are you'll want to/have to change the accessory drive to the F-body style, water pump will fit properly (and use stock hoses), and the truck intake will not fit under your cowl. Just get yourself an LS6 intake (I dont know what to do about the different injectors from the truck harness, a wiring sponsor could help you with that), f-body accessory drive, and F-body pan.
2) ?? No idea. Some companies offer adjustable coilovers as well as different spring rates, enough people put iron blocks in that the aftermarket has it covered for sure.. Look at the sponsors at the right, maybe someone'll speak up in this thread..
good luck
olly