First thing. A 351w swap is a PITA. (Pain In The A$$). The windsor is wider and taller, making things fit sucks. It can be done and it you have the tools, knowledge and some fabrication skills by all means have at it.
Things to be aware of:
Oil Pan. the II has a special pan to clear the rack for the 302 (it doesn't fit the 351) you will need a front sump pan and "massage" it to clear the rack or go with a manual rack. If you use the stock II bell housing then you will also have to make room for the starter that is in a lower position (more oil pan mods).
Headers/exhaust. There are 2 different engine swap headers out there.
Hooker (cut holes below the brake booster and cut out battery box and relocate battery. Each side the rear 2 tubes snake around from the outside to meet at the c
collector.
Heddman makes a swap header but it is more of a "race header" must use front engine plate, no power steering, all 4 tube on each side meet into a flat wide collector.
The standard 302 Heddman header will work with a LOT of modifications. Or go completely custom and have a set made.
The stock 4 speed transmission is not famous for being very durable. Many have been broke behind the 302 they were installed with. If you are very gentle it will last a little while. If not, get a shovel and a bucket for the parts... plus with the torque of the 351w the 10" clutch won't last long either.
I'm not saying it can't and shouldn't be done I'm just letting you know what you are up against. I did it. I think I would have been happier with a stroker 302 and there would have been a lot less problems. To each his own, good luck which ever way you decide to go. If you have any other questions ask away.
The cars were optioned many different ways. With a short, long or even no console.
Good luck,
Tim