One other note - the o-rings on the single coil version appear to be a tad thinner than on the dual coil version. They are a different colour (white as opposed to red on my two units) and the cap is much looser with the white rings on the single.
I know there have been some comments about the looseness which I wondered about since my original dual cap fit so snuggly.
Yeah, I ordered the Dual Coil version but must have gotten sent the Single. It had a loose cap with one hole, and the white O-Rings. But, with a machinist's help and some floss, it's rocking two holes and the cap is nice and tight now. Made my own dual coil version, ha ha, and it's awesome! Another amazing set-up to my already amazing REO, many thanks to Rob, once again.....