1) Don't know what the bolt thing is. I took it off once, it's into solid metal. just a threaded hole.

2) I'm not sure if it is exactly the same as the B18 sized hole, but it is certainly smaller than the aux air valve on the injected heads. Did oil coolers hook up to that fitting? Might explain why it was on the R-sport head.

That was quite an eBay score, really. I think I paid $157 shipped. That head would probably cost $1000 or more to duplicate from John Parker or one of the Swedish shops. BIG valves (as big as you can possibly get without offset drilled guides), hardened exhaust seats, very well worked ports, much larger in the exhaust than my stock B20F head, double valve springs.
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'63 PV544 rat rod, '93 Classic 245 + turbo