Ron - We must be looking at different ewbsites, but I can't find a single PRO 5.0 car that ISN'T using an aftercooler.
In any case, when trying to push higher boost levels into any motor, I would always use a cooler for the added safety margin on today's poor quality pump gas, or to run a more aggressive tune-up for even more power.
For the same reasons as Rick and Ron have already mentioned, I'd always use EFI. To be able to individually tune cylinders is invaluable. Some engine designs always run lean on specific cylinders. With a better carb, you can try to jet that corner differently. This can mostly prevent the sylinder from running dangerously lean, but it then makes at least the next cylinder too rich -- less overall power produced. Also, to be able to tune depending on water temp / air temp / battery voltage, etc, etc is something that a plain ol' carb just can't try to compete with.
http://www.mustang50magazine.com/techarticles/29620/
http://www.musclemustangfastfords.co...Mlords19_z.jpg
http://www.wolferacecraft.com/images...silvanew07.jpg