Does anyone know how much this engine weighs? I'm thinking about doing an LS1 swap and need to know. Can't seem to find it anywhere.

LS1 engine is much bigger (wider, longer, higher and heavier) than a JE-ZE and I can't see how one could shoe-horn it in. It would be a major re-build and there would be serious problems with excessive engine bay temperature (everything in there would need to be fire-proof).
The complete re-wire alone, will cost you thousands... because it will take even a very experienced auto electrician hundreds of hours... and then there is the suspension, brakes, transmission and all the rest.
The issue, of course, is simply... is it worth it?