Decoding a 4L60E

[Nima]

Hello:

I was wondering if you could help me to identify this transmission since I am confused by what I see on it. I was planning to put this in my 2001 suburban with a bad 4L60E.
I got this transmission on CL, and supposedly was rebuild about 8,000 mile ago in but has changed hands between few family members. It was listed at 2002 model in a Tahoe. I am looking at this as an educational experience since I just paid $300 for it and I though I may just use it as core.
So, the tag is missing of course but this is the number on the case": 8KCD115(OR S)L and other numbers which I assume are serial numbers. So, please correct me when I am wrong, based on the number, this is either a 1998 or 2008 tranny behind a 5.3 vortec. It cannot be a 2008 because the two piece case doesn't have the top bolt hole (right?) but it does have a deeper pan which I think came after 2000 model years. It also has green wiring harness connector and I believe the wiring connector changed to black after 2005, so it cannot be a 2008. From the other hand, did 5.3 vortec was offered in 1998? I thought they offered 5.3 vortec starting in 1999.
So, what model year is this? Can I use it in my 2001 suburban with 5.3? Is this a tranny which was just changed/modified?
Thanks