Just my opinion, I would only rebuild the 216 if it was going in a 100% stock restoration and if you was going to show it. If the plan is to just putt around in it, clean everything, hone the cylinders check and reuse the pistons with new rings, check the crank and bearings do what is needed and the same with the head.
This could be a relatively cheap overhaul?
The 216 is not a bad engine for what it is.
We recently finished a total rebuild on a 261 (54 1'st series) thats in my brothers 51 half ton. All machine work was done and all new parts were used. Dual carbs, fenton headers, mild cam, 235 head, electonic ignition. Motor runs great and pulls hard in all four gears. This was the first stovebolt inline six I have rebuilt.
My experience is in V8's.
I have to say I am very impressed with this motor.
Good luck in whatever you decide to do.
