It seems like when I first heard of these they had released them and a few people got them and then MSD pulled them again. Not sure why or if this even true but this would have been many months ago.

 

A couple of things to consider since your possible combo is a '93:
1) It is a speed density setup (vs mas air flow) & the wiring, etc. is different than the 94-95 OBD I & 96-97 OBD II setups. To modify the computer, you have to have a chip burned vs. being able to interface the computer via the ALDL port.

2) The '93 T56 had a higher (numerically) OD 6th gear, .62 vs. the .50 of the 94-97 ones. I believe it was only rated to 400 TQ vs. 450 on the later ones.

I stil have an LT1 converted to LT4 with a "bulletproof" T56 in my '95 TA & love it. I took the original motor & T56 from this car & it now powers a 1975 280Z.

Having said that, the future is in the Gen III motor.

I'm doing a '88 Supra now & just bought an entire (less alt/ac/ps/brackets) 5.3L w/ 32K miles from a JY for $400! The least I could find an LT1 similarly equipped was around $5-600, and they all had like 80K+ miles. The 5.3 in stock trim makes 285 HP, same as the 95+ LT1 w/ dual cats. It gives up some TQ, but the mods are easy & great bang for the buck as you will find out from being here.

Good luck w/ your swap.

 

The biggest problem with the 5.3L truck engine is it doesn't fit under the hood in stock form without changing the hood to a 2" cowl. You can change the intake, water pump acc brackets, and pan to the ls1 F-body style but that just adds to the expense and work. So yea I looked into it, I can get a complete 5.3l from a 2003 Truck with under 20k miles for $800 locally. But then a guy has to find all the other parts to make it fit in the car.

I appreciate all the feedback. If anyone is interested in a '93 LT1 with 25k miles since rebuild in 2002. Pm me and I will give you the guys information. It comes with a 6 speed tranny too... he is asking $1k but will likely take less.

Also, check here for a sweet deal on car parts including LT1, LS1 and 6 speeds... http://66.15.92.42/cgi-bin/usedpartsdepot.pl Use the tool to search multiple years (they differ quite a bit) If anyone buys from this site (Used Auto Depot) please let me know how it works out. I've never used them, but some of the prices seem good and they can get almost anything. I'm in no way related to them, just passing on some info I've found.

BTW, I am pretty sure I am going to chicken out of the swap all together and build my 400 more.

Thanks for all the good information, it's just more time than I can dedicate right now.

 

Prices seem to be hot or cold....
(From their FAQ)
How much is shipping?
All Ground Shipping charges of automotive parts are included in our price. Most items ship UPS or USPS. Larger items may ship by Freight companies and company trucks.

Did some shopping:
1997 T56 $399 shipped! (selling here $1000+ and shipping)
1998 LS1 motor $907 (selling here $1500+ and shipping)
1998 LS1 intake $438 (selling on Ebay $30-50 and shipping)
1998 LS1 oil pan $124 ($167 new)

I'd be interested to hear if anyone buys from them as well.

 

Personally I'd save the cash and do the LS1 swap. I've done both the LT1 & LS1 swaps and the only additional items for the LS1 to worry about are the tach, (speedo depending on tranny selection), motor mounts and oil pan.