overheat only over 3000 rpm
Shouldn’t matter in this instance, for several reasons
-pusher fans on the front can’t have a shroud
-lack of a shroud with a mechanical fan will hurt low speed cooling, not highway speed cooling
-a factory shroud won’t be blocking enough air flow to have an air stack problem at highway speeds
The only scenario I could see that would contribute to the over 3k rpm, highway overheating would be one of those flat, cookie sheet style aftermarket shrouds with an electric fan. But that would mean he’s running pushers and pullers, which would be a whole different can of worms