I feel like this is going to be another one of those disaster threads. Detroits, especially the 53 series, have more moving parts than any other engine. It not only takes knowledge to build these...…..it takes the proper tooling. If your engine got hot enough to crack the cylinder head it has flattened the liner seals. From what I've seen so far, it looks like an inframe overhaul candidate (providing the oil pan can be removed). Keep in mind, the work on the replacement of the needed parts isn't the tough part...…..its the timing, fuel rack settings, buffer screw setting, injector heights, valve bridge adjustments, etc...….that are critical to the proper operation of your engine. The type of governor will determine how you do your fuel rack settings, whether it a double or single weight, variable or limiting speed, open or closed linkage.
If your up to the challenge then I'm game as I'm sure there is more experience here than you will find in a service manual...…….but a service manual would be mandatory to me before you get started. Just know this can be tedious work, and getting the set up right can be very frustrating without having experience on Detroit engines. If you try to shortcut this, it WILL bite you in the ass.
So with all this being said...……….do you accept the challenge? I would expect to spend 2K on parts and tooling to do the job yourself...…..maybe more. If you elect to replace your engine make sure you get the proper build. These engine can look alike but they can be built in many different set-ups and rotation can be either left or right.