Need help ID'ing transmission 7KCD153A

[Bullfrog]

Hi Guys, brand new here so be gentle. I have a 1997 Z71 3 door that I bought used some time back. I'm pretty sure that neither the transmission or engine are original. The transmission bit the dust and I need a replacement. The transmission is still in the truck so I can't read the top ID tag but I can see what looks like a vendor rebuild tag. The case is stamped with 7KCD153A which should tell me what I need to know. I can't find a decode for this, anyone point me in the right direction? I need my truck back on the road. BTW, the reason I suspect the engine is not original is because the VIN specifies 5.7L, but the Oil Filter that is called for with thread size 18mm x 1.5 will not fit. Oil filter with thread size 13/16" -16 does fit. I haven't pursued that yet. Thanks!