Guys, I'm trying to help a friend get into S/S or Stock racing. He recently came into some money & is looking at a V-10 Drag Pak Challenger. Yes, I know it's expensive ( he's also buying a T/S car!

) but he can afford it. Just what class do these things run in? Who are the "go to" people for V-10 race engines? Just how successful are these cars, really?
He's a big Mopar fan but I just can't see throwing money at this thing unless he has some chance of being successful. Myself & another guy have some experience in the Super classes but now we've been asked to help (possibly) with this effort.
Any opinions?