[Lynn Eades]

Rich, your radiator is not a carrier radiator. It is from a car or light truck.
Your top tank spigots should curve out and down. It is also important that you have the correct bottom spigots (they can come from the bottom tank at 3 different levels)
The top mount is basically flat (not to accept stay rods)
If you are going to have one built, there are some advantages.
You can have one built that will cope with a higher pressure.
You can have a neck fitted to take a modern pressure cap (try finding a good original)
You can have a more efficient rad.
A modern neck and cap is much easier to use than the original (though not original.
if you do spend the $$$($) carefully inspect your fan and fan extension mount stud. I have heard from more than one person who has suffered acute trauma in the fan and radiator department.