I'm not really following you here. You would remove the head from the truck to drill the broken bolt off and put it back in 1hr shop time?
Sorry for the confusion. I'm saying given the choice of installing a threaded insert into the head, or buying a new head I would choose the threaded insert. Either way the head has to come off. Once the head is off, the 1 hour shop time to install the threaded insert would be significantly cheaper than a new head.
Also, someone had posted their valve clearances after doing valve cover gaskets not too long ago. All of them were right at the tight end of the spec from the FSM. I believe he had 180k or so miles.