Javelina, like deer, are much easier to skin and butcher when they're fresh killed. There's not much meat on the shoulders, but the little hams are great when slow-cooked barbecued.
I always started with a bunch of basting, and a very high heat to sear the outside to hold the juice in. After maybe five to ten minutes at most, I'd spread the coals to the equivalent heat of maybe 300 degrees. Turn and baste frequently, using tongs, not a fork. After a couple of hours or so, they're in the vicinity of well done, but not at all dried out.
Delicate, yummy flavor.
Picking out which javelulu to shoot makes a difference. Look for Ol' Biggie, but shoot one which is maybe two inches shorter at the shoulder. Younger, less likely to be gamey.