Ok, then the numbers are very similar (identical) to the older version. You don't have to open the engine and look at the transfer ports, if you have the version with different diameter cooling fins it should be the later version with proper aligned ports. Yes, it would be ABN rather then ABC, but I would still have liked to have had a snugger fit at TDC, never had an ABN that improved after running...

The backplate has no seal so I've put teflon tape to seal it (more as a precaution rather than actual problem). The restricted breathing is a problem for high revs in glow but will probably be just fine for the revs used in diesels, might be an advantage even. Looking forward to hearing the progress, I still haven't been able to get any diesel fuel here so I'll have to stick to glow...