You can purchase both long- and short-block 6.3 motors from Metric Motors in Southern California. You have to call them (Google for their web site) for quotes as they don't list them on the web site.

Your best best, as Dan says, is Star Motors as 6.3s are the bulk of their business and they know them inside and outside better than anyone out there.

Again, the old adage applies as Dan and I have said since day one on this thread: when it comes to a 6.3, if you have the ask the price, then you shouldn't own the car.

it's very difficult to kill a 6.3 motor. Yes, the peripherals, alternator,water pump, thermostat, brake system, hoses, ignition, belts, motor mounts, fuel injection pump, cooling system, yes all of that stuff goes out. It can also be rebuilt as well because it's mechanical.

The actual block and head of the 6.3 are pretty close to as bulletproof as an engine can be as long as they have an adequate supply of lubrication. Some did, some didn't.

it sounds as if some time spent on the phone with Neil Dubey would be time well spent in assessing where you are. Personally I would have had answers to all of these questions BEFORE purchasing the car, because it would reduce the potential for expensive mistakes and time-consuming detours to find vendors and places that can do the work. But as some say, "the journey is the reward." Perhaps Dan subscribes to that philosophy too.

In any case, I think a thorough, early morning or evening conversation with Neil Dubey at Star Motors would take care of your needs for information you seek here. He doesn't charge for consulting time, and is plenty happy to make suggestions and answer questions.

Cheers,
Gerry