Dan, that seems to be correct. Here's what I have come up with from discussion with multiple sources, and seems to match what I am finding on my 1150.
Frame, engine, major castings, body, platform, etc. were Flint Gray Metallic. I have found a few odd pieces, like the seat arm rest wrap around, that are just plain Flint Gray. The high backrest support also appears to be plain Flint Gray on the inside where it is still intact, but I think mine is going to be Flint Gray Metallic... The Grill was Silver MIst Gray with the black horizontal screen stripes. Also, the side supports on the seat were Silver Mist Gray.
If anybody has information that any of this is not correct, please speak up so we can all learn!!
Thanks,
JB