You are on the right track, but it is always impossible, and actually unwise to order parts before disassembling and examining/measuring.
Once the engine is apart, you need to take the head for valve job, always including valve guides. DO NOT mill this head unless it absolutely needs it, which it probably will not. This is a diesel with a VERY SMALL combustion chamber, and it is iron, rarely needing to be milled. If it is a little unstraight, the machinist must proceed very carefully.
Secondly, mic the crankshaft to ensure that it will take standard size bearings which it probably will. The last engine of this type I took apart, I was able to reuse the original bearings.
You will then need to let your machinist test the block by seeing that it will clean up at a diameter less than the first oversize. At this point you will know whether to get pistons/rings in first of second oversize. Make sure you buy the pistons with the correct piston crown shape. There are two different types and they will not interchange without changing to the appropriate prechamber. Be careful with this.
Some people reuse the pistons and resleeve the block back to standard. If the pistons are in VERY GOOD condition you might get by with this. I personally do not prefer this method given that the pistons in a diesel are highly stressed.
I would plan for
timing chain, and associated parts,