Great looking restoration!!

Did you have any problems getting the Odyssey battery and Marvel carb approved?

I'm nearing the end of an 11-BC Chief restoration using the Wagner STC and an O-200. Lotsa work/$$ in the o-200, and I'm now hearing some disparaging opinions about how it compares to the "super C-85." The tandem Swoards STCs would (I think) let us turn the O-200 into a C-85 by installing a C-85 cam and lifters, with the "super C-85" (O-200) crank, etc. Among the dollar drawbacks would be using a C-85 stromberg, so your use of the Marvel sounds encouraging! Of course tearing down a prefectly good O-200 that's already installed on the plane feels pretty disheartening, so I'll probably fly it first and see how I like it. Good to see you were able to sub a Marvel for the Stromberg and get the Odyssey approved, though!