If you are speaking of me, I have a T56 Magnum... so would work fine with the LSx setup. Would need a few scattershield though...

So are you saying that I can just change the bellhousing to the LS and it will work?

I thought the T56 that works with the GenI & GenII motors have a different input shaft length.

I decided to go a diferent route than a crate engine...
 

I started looking at going with a crate engine and off the shelf tranny, then buying all the associated parts for DETONATOR, and after realizing just how much I would have to buy, getting a compete wrecked car was going to be the most economical choice, for my situation anyway. Side benefit is selling parts I didn't need to get some money back. And I'm using the seats from the wrecked late model and the dash. Sorry to get off topic, this is about the drive line...

I've got the drive way for two dead cars, not everybody has that luxury. I also have the luxury of an understanding wife, big luxury there!!! Another factor to consider.

Still need to buy headers ($500-800), oil pan/oil pick-up tube/oil filter set up ($400-600) and some MAF/intake/air filter parts ($0-???). Wiring harness needs to modified ($400 to 800), and computer tuned, or you can buy a Painless replacement harness/computer ($700 - $900). Not sure about AC at the moment. I am going to try to reuse radiator, all engine accessories and pulleys, hydraulic clutch master/throw out bearing, stock clutch setup/bell housing. DETONATOR has a Chassisworks replacement sub frame, so the motor/tranny mounts were part of the subframe package.

So there are a few costs that will be there no matter what, however if you are mechanically inclined and willing to work through re-engineering stock GM parts you can save some serious coin. One benefit is all the parts that come off the donor car work together, and there are no headaches from buying the wrong aftermarket part, returning it and swapping parts until you get the right one.

Also out here in the California Bay Area , there is a place that will pull a complete engine/trans combo from the radiator hoses to the engine tail shaft, modify the harness/computer, etc. for a set price, including pedal for throttle by wire applications, Pacific Fab. The package is pretty much plug and play with a few wires to connect to the engine/trans, connect up the hoses and you are in business, and it cost less than the cost of just the crate engine and tranny.

New is good, I understand why you want to go that way, and the waranty on the engine and trans starts when you buy them, the clock is ticking while you get all the parts together and then finally get it runnuing.

Just my 2 cents...

If you are patient you can do the harness yourself. I started with a stock '04 Vette harness with DBW. I did mine and it seems to work fine.
Then I had Tom M reprogram my PCM I think it was $250 plus shipping. He is always on LS1 Tech and Steve's Nova Site. Great guy.

The LT and LS style T56 trans are different. The input shaft.

I think the greatest difference is the $1200.00 core charge. The performance engine does not have one.