deadbeat son
Explorer
Do they fit without any play? If they truly are 108mm hub centers then I could definitely build a set out of the spare 16" like you're saying. Here is the list i've been referencing for Toyota, most are 106mm:
They seem awfully snug to me, but I think it would be difficult to notice 1 mm of play on either side. I tried to measure the bore in my 16" spare wheel, but I couldn't fit my calipers in there. They spread too far and hit the edge of the rim.