[Naja]

The exhaust gas in coolant was determined very early on after it became runnable (in December) - actually, the day after I got it safety stickered, because that was the first opportunity to run it for longer than 5 minutes. And, yes, #7 & 8 were 20% and 30% on the leakdown test.
No definitive cause(s) for the exhaust leakage, so the builder thought it may have been several small points. He also thought that the block was slightly twisted, causing the cylinders to be very slightly out of round. Of course, the engine was pulled and torn down. Heads and block re-levelled, and cylinders re-honed.
That was 6 months and 1500 miles ago. The various overtemp problems have kept me from having 5000 miles on it. It's been in shops for at least 4 of the last 8 months. (It's in the shop right now to rebuild the transmission because of metal particle damage - source unknown as of today).
Having a continuous string of problems for years sound familiar to anyone???