rebello240z

I have a few questions for those people who own or have done a f-54 swap into any Z car.
First off, are the water pumps interchangeable with an L24? I thought they were but a friend of mine says otherwise.
Two How strong are the f54 engines? how many miles can i expect out of one?
The plan is to pull a lowish mileage engine from a junk yard and put it into my 71 240.
what head does everyone recommend for this and will MSA 6-1 header fit onto the F-54 head. be either a p90 or an n54 or a p79 it is on an e-31 right now.