Gear Housing Valve

My friend's 98 Cummins has over 200,000 miles on it, and he just moved onto a very rough dirt road. We never thought about it, but I read an article in my diesel magazine about the dowel pin causing the destruction of many a Cummins. Now he's freakin out because his truck fits the bill and his road is almost always wash-boardy and rutted out. We've inspected the crank housing and there's no cracks and there's nothing in the oil pan, so we're assuming the little bugger's still in there. He got to looking into the problem and now he's paranoid that each bump is gonna knock the thing loose. I know what can happen if the thing hits the crank gear at 2000 rpm, and he especially doesn't want to see his beloved Cummins sent to the scrap heap. He's considering buying the repair kit, and I was wondering how much work this is gonna be, I know the whole front of the truck and the engine have to come off, would it just be easier to take it in? Thanks for the help!