swap out
 

can u take a 5.0 from a 91 cougur and put it in a 96 f 150 with a 5.0

Yes but you will have to transfer over the oilpan and pickup, complete intake system, timing cover and water pump, balancer and distributor, and accessory brackets and accessories from the outgoing truck motor to the new stripped down donor motor.

So basically Cougar block and heads, everything else truck parts correct? Are there any pros/cons to one head over the other?

Both engines should have the same E7 cylinder heads.

Ok thanks. I wasn't sure if there were any differences in the valves, springs, etc. And if anyone else didn't know, now they do :-X06

Arn't the 5.0 cougar engines HO? And they have a differnt firing order than a regular 5.0?

HO is just the 351W firing order. I didn't think that all cougars had the HO.