Upon head removal, head gasket failure was confirmed. I couldn't make Sunday but according to Dempsey inboard head bolts didn't take much force to unbolt. So, it seems quite feasible that failure may have been due to improper torque when the short block was assembled at the machine shop. Another possibility raised was detonation in #5 and #2 cylinder.
Heads are being shaved and cleaned and we will be making sure that all liners are level and have correct projection above the deck.
Another concern I had was very low oil pressure after the rebuild/install last year. I had about 10 psi at idle when the coolant reached 200 degrees. Well, guess what showed up in the oil pan?! - crankshaft oil plug!
In a way, head gasket failure was a blessing in disguise - forced me to pull the motor and resolve not only blown head gasket but also low oil pressure concern.
For those planning on off-set grind mini stroker crankshaft, make sure to instruct the machine shop to install plugs after the heat treatment. Rich (Scrrem) had the same issue.