Where to start with mods?
Gauges are always a good idea - especially if you tow.
The SCT is probably the best choice for a tuner. A tuner with the electronic gauges is the "Phalanx". It is based on the DashDAQ unit. Spartan diesel is the only place to get a Phalanx, and some folks have had trouble getting customer service from them. Others can tell you the best place for an SCT tuner, but Innovative Diesel is one. Also - River City Diesel sells them and so does Power Hunger Performance IIRC.
Head studs are expensive - only you can decide whether or not they are justified (assuming you are currently not blowing coolant out the degas bottle).
Many folks say that with a tuner it is inevitable that the head bolts will weaken and you will blow the head gaskets. With that philosophy, ARP studs would be best BEFORE you have an issue.
Anyone use the Spartan Phalanx Console on a 6.0? - Ford Powerstroke Diesel Forum
IMHO, i would start with gauges, EGT, EOT and ECT, watch your coolant levels, i've heard some things about coolant filters for our trucks
Cat, Muffler and EGR deletes are nice if your state will allow them







