New LS1 Owners - Newbie Tech - 5.3 engine interchange?

My brother needs a engine for his '99 5.3 Z-71. The truck is nice, so he wants a low mileage used engine. I believe the direct interchange is '99-'04. I've also heard that '05 and up can be used but requires some changes mostly with regards to the number of teeth on the crank trigger. I was told there's an electronic box to do this. Can anyone shed some light on this project? Thank You!

you are correct! direct swap!

you are correct! direct swap!'99-'04? What about '05 up in a '99 truck? I've found an all Al 5.3 out of an '07 TrailBlazer with 1000ish miles. What will it take to get it in the '99?

i think you need a 58x conversion but I may be wrong... Contact efi connection.

Lingenfelter sells a box that will convert the crank trigger signal so the older pcm can read it.

That damn box is $250! I assume there is no budget way to do this? If not, I'll just stick to '99-'04 engines.

All the engines in the GMT800 trucks are 24x trigger. That means 99-06 and 07 classic.
The other variants like trailblazer may have switched earlier.

All the engines in the GMT800 trucks are 24x trigger. That means 99-06 and 07 classic.
The other variants like trailblazer may have switched earlier. That's a black crank senor right? I read the grey ones are 58x. Were is the sensor located?

The crank sensor is above the starter on the truck engines. I think it is in the front cover on the LS2.