Hi Cal

Although I'm not actually building the DeAg Victory I've had a quick look at the official build pages. If the jig you mean is the one to wire the deadeye up on, you may be all right or you might need to make an adjustment or two!
If you have the chainwales wooden pieces, check the bottom loop of the brass wire to see if it will allow the deadeye to sit on the 'platform', if it does, no problem!
If it's too tight to allow that however you'll either have to re-do the brass wire on a 5mm jig or else, if you have a rotary tool with a ball headed grinding tool you could gently sculpt out a semi-circular depression at the bottom of each slot which would allow the brass loop to fit in place, this could be hidden with some edging strip around the chainwale once all the deadeyes are in place.

Best of luck, but if you do need extra brass wire there are some good cheap suppliers on e-bay (that's where I generally go for mine!)

Robin