I think you can do the conversion for about $3500 if you do it correctly, minus a/c. You could do it for much less if you shop around. Don't fear a 100K engine, those are just broken in.

$2000 engine and transmission
$50 engine adapter mounts from Ebay
$800 Custom engine Harness and fan harness
$200 Electric fans from 2005 Silverado at GandRauto.com
$200 New aftermarket 34" radiator
$20 materials to make mounting brackets for fans and radiator
$60 new radiator hoses... 3/4 2005 Silverado hoses
$150 hotrod tune to remove VATS and non-essential smog diagnostics
$70 silicone intake elbow reducer
$60 K&N air filter
$650 Street and Performance hi-right side a/c relocation brackets and Sanden 508 compressor
$100 custom a/c hoses built by NAPA
$200 custom exhaust

if you have a single inlet fuel rail, you'll need a 2000+ Corvette internally regulated fuel filter and quick connects.

$60 fuel filter listing on main conversion page along with connector part numbers
$28 (2) 3/8" female quick connects
$14 (1) 5/16" female quick connect
$12 (1) 3/8" male quick connect
$5 one foot of 5/16" fuel injector type hose
$30 six feet of 3/8" fuel injector type hose


Depending on what you can do on your own dictates how much your conversion will cost you. Some guys notch/box the frame to use the stock LSx a/c unit, I just pay the extra money for the S&P unit since my welding skills are not that great and I don't care to weaken the frame any.