3rd and 4th gen engine compatibity

Aloha, first post here. I've been lurking for a while now, and while I know alot of the parts are interchangeable, I've haven't seen a definitive answer for the question: Will a 3rd gen engine fit in a 4th gen frame or visa versa? TIA. Mahalo, Les.

 

Definitely yes and vice versa.

 

I know for a fact the water pumps are different! possibly the oil pumps are diff also

 

Aloha and thx for the quick response. I just needed to know if my 91 VFR engine had the same mounting points as a 4th gen. It may sound like sacriledge to some of you here, but my plans, as of now, are to transplant my viffer engine into a 3rd gen Magna. Just love the sound of the gear-driven cams. Mahalo nui for the input. Les.