It's hard to say not knowing that market, but the thing has a lot of extras on it and it's a pretty nice looking truck, but the engine is a trot line sinker.and i don't care what the guy says about how good the thing runs bla bla bla, if it's got a blown head gasket, as far as I'm concerned, the whole engine is a trot line sinker. A truck with an engine that is not fully running is a NON RUNNING VEHICLE no matter how you try to fluff it up, and in this economy, the guy can wish all day long and he's not going to get thousand dollar bills jumping into his pocket for a dead truck. If he wants top dollar then he's going to have to fix the thing, otherwise he's going to have to take what he can get. Make sure to bring cash with you cash talks BS walks.
I'd give him $500 for it but then I'm a cheap old ******* , It might be worth as much as $7-800 in that market if the interrior was clean, but are you saying the cab is shot on this thing ? If that's so, I'm sticking with my $500. Bring a stack of $50 bills and wave them in front of him ( if ya REALLY gotta have the thing have a few extra in your pocket )
If you can get a good 7.3 for $700 to drop into it, that would be a good deal, it might run you more than that for head work when you pop the heads off that thing. BEcause it would be stupid to just slip new head gaskets in without at least having the heads inspected and you would most likely find they needed a handful of guides and a valve job etc, it could wind up $400 a head by the time its all said and done.