as long as you have the registration, I don't think you need to worry about the HIN (hull ID number)..
But, as long as you have the paperwork with you where you sent in for a transfer to your name, the wardens should leave you a lone.
We were all checked at our tournament this past saturday at Yahoola by the DNR, and I took my wife there again today to show her where it was... the game warden was there again. That makes 4 out of the last 6 times I've been, that same warden has been there checking licenses and registrations.
One of the guys fishing with us had expired tags, but he had the paperwork where he sent it in months ago... another guy didn't have any registration stickers and he got a fine
Call down to the DNR and talk to them, they will tell you exactly what they need to make everything happen.. they keep changing the rules, so best bet is to call and talk to them