Whoops, my bad. I meant to include a link to the refrenced article but forgot. Hey, if it DOES bolt into the 9" without any effort then great, once again before relying upon anything a vendor has to say I would contact the companies tech line directly and speak with them about it.
http://www.4x4wire.com/reviews/d44lockright/installation/?
But beyond that, I have to ask, why bother dumping *anything* into a truck you're looking to sell ? Now I can see making needed repairs but quite honestly I question the wisdom of making upgrades that cost hundreds of dollars and simply aren't required. Tuck that money away and use it to buy the truck you DO want. Granted your current ride won't be as capable as you'd like it to be but is this upgrade really going to add anything to the resale value ? At the end of the day it's just money out of your pocket. You may want to consider just cleaning it up, keeping it nice and then spending the extra cash on your next truck. Throwing a locker in there to take it out 4-wheeling isn't *really* the way to treat a truck you're hoping to sell for as much as you can get for it. There are a LOT of ways to mess up your ride out on the trail. Personally, I'd leave the thing be and treat it well until you hand it over to the next owner and then let HIM go & beat it off-road.
The number of buyers out there who will have *any* idea what this locker is and does is pretty small. More likely what you'll find is that explaining it to someone will turn them away because they're concerned about you *upgrading* the axle all by yourself in the driveway. Lots of buyers shy away from upgrades like that unless you have reciepts from a professional shop indicating (to them) that the work was properly done. Right or wrong that's just the way a lot of people think. I've walked away from trucks that were modified at home by guys I didn't think were qualified to do the work. I'm not saying for a moment that you can't do this & do it well, just understand that a lot of buyers may have a different perception.
Throwing $$$ into a rig you're looking to sell is rarely a winning proposition. If it ain't broke then don't fix it. Wait until you have the truck you want & then dump your heart, soul, money & blood into THAT one.