Oh, I get it. You want to search by equipment, not by route.

No, I don't know of any tool that does that. I think the best thing to do is become familiar with the schedule for the airline - you'll get a good idea of what types of routes the planes generally fly. As far as random last minute substitutions - since they are random and last minute, there's really no way to search for them. What I'm saying is, even on those days where you got a 777 EWR-MCO, the flight may not have been "listed" as a 777 so there would have been no way to search for it.

Sometimes serendipity works...