I have a 2008 WNP 18LT. As for the spare, I started to make a bracket to put it on the tongue, then I got a tongue box and gave up. I am now looking at mounting it under the tongue box, between the tongue rails, but that is far as it has gotten.
As for mounting it on the front, you would have to drill all the way through and have bolts somewhere on the inside. I did this to mount a television in the back corner. The walls are 3/4 inch plywood with a fiberglass laminate. I saw a picture somewhere where the spare was mounted inside, left rear as viewed from the rear, against the inside wall. Also without measuring, I'm pretty sure the lug pattern in 5 on 4.5. You should get by with only three to mount the spare. If outside, I would have one of them a locking lug with a special tool. Good Luck, and let me know what you do. My spare just rides in the back of the truck for now.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT