Steve,
It is best to describe your "comfort level" in your skills and/ or acess to people with skills to do any engine work, etc
I always tell people to ask themselves, what are your goals and driving expectations with the car, as well as budget?
Those two things, basically answer your question
If you are limited on skills, tools or people to do the added work, stick with a crate engine option
Or look into the many builders that can build you a engine to fit your needs
you can choose between Gen III or Gen IV setups and pcm's (effects some harness/ pcm, tuning prices)
examples (not promoting, just a fyi)
http://www.thompsonmotorsports.net/p...roducts_id=206
http://www.thompsonmotorsports.net/p...roducts_id=207
As mentioned earlier, if the new engine warranty is a main factor, then cracking the engine open to install a larger cam is of the table, due to voiding the warranty
Also, look into if even swapping the crate engine oil pan, effects warranty??
Not sure on that
Also, check with some tuners and find out how adaptable the GMPP pcm/ harness setup is to engine mods?
some earlier versions were only good for the GM configuration
Plus, there are so many other aftermarket companies selling the pcm & harnesses (some cheaper than GMPP setup) and can get up up and running with a "base/ mail order" tune, then either dyno tune or remotely with a setup like EFI Live Autocal, etc
Hope this helps
Jeff