Originally Posted by KAdams4458

Updated pencil plugs or not, the old loop plug glow plug chambers still need to be cleaned out, and that means a reamer is required. One could probably get away with just screwing the updated pencil plugs in where the loop plugs had been, but there could still be a ton of of carbon in there.

As for using a bore brush... Yeah, that would probably work great. I'd just be worried about loosing a bristle in there. A reamer would be much safer and more efficient.

Do you actually have the larger reamer? If so, would you be willing to share the dimensions?