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Ask yourself why not, not why.
79 engine and the heads did not need the mating surfaces touched? Was that because they didn't need it or that they were not considered. Each head should be measured for their heights.
The case decks need to be measured for their dimension from main housing centerline. You should check the decks for flatness and parallel in both directions. Then you can measure the cylinder liner heights as well. This gives you a fixed deck height number from crank centerline, up to the cyl head. This can be considered your block deck height in any other type of engine. You need to establish both sides are the same. You can adjust any differences with the case deck, or by shimming with base gaskets. This is now your block deck height.
Now if you cannot measure the each rod crank for its stoke, you can now measure each rod CCL, and piston comp height. Assuming that the strokes are the same, you can calculate the piston deck height from theses parts. From this dimension you can establish on paper if you have a negitive or position piston deck height and how much that may be.
Now when you actually measure the piston deck height it should be what you calculate and they should all be the same. Remember, measure the deck height across pin axis, not as shown in the photo here. This takes any rock out of the piston.
Now if you measure the chamber volume and the piston volumes you can calculate your actual static compression. It is always a good idea to do this as often stated CR numbers are quite difference to actual. CR numbers can be adjusted here to with base gasket shimming.
But if you have not checked the case decks are flat and the same each side, you will have CR numbers all over the place along with differing piston deck heights. This is a street engine so you will see some differences, and so its up to you to decide what is acceptable.
If you need help in any of this, I can answer any questions.
Leave nothing to chance.
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