^Curly is notorious for having a very hard skull. Numerous saws and axes have been ruined upon contact with his cranium, and on one occasion Curly was the one left standing following a head-on collision with a bull. So the laws of stooge physics would predict that Curly would come out on top.

Of course, the stooges are also known for running at the first sign of danger, and generally cower in the presence of anyone with a significantly loud and/or commanding voice. So it would take a lot for Curly to get into a head-to-head confrontation with a large horned dinosaur, especially Mr. Threehorn.

If the stooges ran into the three pachycephalosaurs from the first LBT, though, they might be more inclined to turn and fight.
I suppose if I'm going to post in this thread, I should add my own crossover suggestion; how about LBT and
Primeval? (As far as crossovers go, that's one I'd like to see.

)