I have a 1992 GMC K1500 with the 5.7L V8 and Trying to find out if small block LT what?

The 1992 GMC K1500 5.7L V8 did *not* use a small-block LT engine. The LT series of small-block V8s (like the LT1, LT4, etc.) were introduced much later by GM. Your truck uses a generation of small-block Chevy V8 that predates the LT series. It's likely a TBI (Throttle Body Injection) version of the small-block, often referred to as a "small block Chevy" or sometimes a "Gen I small block" in reference to its place in the family tree. You won't find an LT designation anywhere on it.