Hi Keith,
As discussed in your earlier thread, the problem with using newer type oil rings in these older (pre-'54) 235 engines is that the sets are harder (but not impossible) to find. It seems most new complete replacement ring sets for the 235 are for the '54-up engines, which use different size compression rings.
If you don't want to/can't spend the $ on a full new set, I don't see why you can't/shouldn't use the NOS set with the one piece oil rings. They'd probably last quite a while if the truck is driven as little as you say. All of the 216/235/261 engine family originally used the one piece oil ring (I think), though improvements were made over the years. For example, in '54, a new spiral spring type of expander was incorporated into the back of the oil ring.
If you decide to go modern, I had mentioned in the earlier thread that Hastings Manufacturing (hastingsmfg.com) makes ring sets for the pre-'50 235, with what they call a "Flex Vent" oil ring (a "revolutionary" ring that they introduced to the World in '56). They have a warehouse in your neck of the woods, in Minneapolis. I also found a set listed by Deves Piston Rings (deves.com), with modern-type oil rings.
