With the LT1 you would have to get the box, but I think most junkyards would sell them together. Plus once you get it in there, it is rated at something like 300 hp. That is before any mods.
The other idea is to take off the crossfire intake, change the heads for some better heads and install something like a holley TBI system. You might even be able to do quite a bit more by pulling the motor and changing the pistons, I don't know what they are like.
I don't know what Utah vehicle inspections are like, but you might even be able to go with a carb if cost becomes an issue. But I would change the heads if it was me and I had the money.
If it is an auto tranny don't forget the idea of a shift kit.