It depends on which Wilwood kit you installed. Some of them move the front wheels out by as much as 3/4", as moparman pointed out. Some don't change the offset at all. Do you know the part # for the Wilwood kit?
17x8" with 4.5" of backspacing is pushing it to begin with. I know the later A's better than the early one's, but most of the early A's I've seen run 17x7's with ~4.5" backspace. If your wilwood kit moved the front track width out, you probably don't have enough backspace in the front. For a 17x8" I'd guess you'd need more like 5" backspace, and if your wilwood kit moved the wheels you'll need that distance added to it.
Here's a '65 with some 17x8's up front, but he's using a 5.25" backspace up front. Don't know how much his disks move things though...
http://www.forabodiesonly.com/mopar/showthread.php?p=1970473878#post1970473878