I've been running a 291 for 20 some years in my 40 coupe and have no complaints. It runs at 150 degrees in any traffic. Went to hot heads hemi for a rebuild kit, 727 trans adapter, 4bl intake, headers, and modified cam for chevy water pump adapter. It's not a ground pounder, parts are high, in the end its a great, dependable motor.
always loved your 40. i have a 291 in my chopped and channeled 46 ford. i later picked up another 291 for a hot rod project but ended up selling that one to kirk hanning. had a 354 also. i do have a 241 red ram and a 259 poly block for a future project. poor man's ardun.
I've got a 56 330 out in the shed that I took in trade 30 something years ago that I should find a new home for but it no doubt needs a complete rebuild now.