Hey Gus... The CC306 is a high reving cam.. Makes power to around 6800 rpms.. Not the same low end like your stock one.

The make the most use out of it you'd need some 1.6 roller rockers, and springs, retainers, etc.. Total on parts would be about another 600 dollars ontop of the cam. Timing set gasket kit (15 bucks) and some other odd ended stuff.
Spring seat pressure should be around 140-145 lbs. Your lifters are rated for 155 lbs... so make sure you check the rollers on the lifters to make sure they are fine. Luckily GM made some good quality lifters.