Rebel, Nigel,
You guys dont realise what a good deal you have got. Four years ago when I got my motor and gearbox I shelled out $12K as the LS1's (5.7) were a as scarce as a virgin in a brothel.
A six litre engine engine even in std form s going to be awesome.
The later model engines are much stronger and have better oiling than the early models. Just keep the revs below 6500 and they will last a long time.
Make sure you fit an
oil cooler though.
Regards,
Phil.