Stoker; I will try and get a copy of my Solar Engines company letters posted here later.
{both letters from Clyde Griffin and John Griffin state that they haven’t got an “Owners Manual” printed yet, but will send it in “a month or so”.}
My ca. late 1977 engine is #68** and it had the original box and mid Jan 1978 UPS post mark. Thus I assumed about 95% chance it was made in late 1977, arrived at owner couple weeks into Jan 78’.
The Solar Engine company address on the box label is “Indian Tribal Series , 2937 West Indian School Road, Phoenix , AZ, 85017”.
In meantime; here is screen capture I made from a completed ebay auction with FEB-March 1978 date stamps, #7614 engine number. The literature has Griffins’ name in header, West Indian School Road as address, and looks like the Owners manual was finally included.
