A small update. I didn't really want to publish a photo just yet as I'm right in the middle of the engine, but the day has come to an end and so I might as well. A lot of the flaws will be carefully hidden under paint.
I moved the Cam Shaft housing back 1/2 a "block" to faciliated the roker arms as in my reference photos. I have seen a Mercedes D??? engine with the rockers where Roden has them, but that seems like an early engine. Anyway, mine is fixed in place and she ain't moving.
I rotated the right side spark plugs aft a bit as in my references also. Removed the Roden spark plugs and installed my "Version". Q-tips and wire.
I didnt have any hex bolts nor a hex punch..........so my bolts have all been over tightened and have been rounded off.
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I don't think it will matter much when "Peeking" down from the top cowling when done.
I had to scrape and cut and sand to get "air" between each cyclinder housing. Mine came with a lot of flash there.
Hopefully I am "close" to a Mercedes DIII here..............but it was fun getting here. Roden provided a very solid foundation to start with.
Got to get back to the SE.
Regards
Steve