Two years on and it is still working, I think that second bolt was for a toilet bowl flange.
Last time I used the mower it was running rough. So in the spirit of good preventative maintenance I put it away until I had some time to look at it. It would appear that the bolts that hold the carburetor had evaporated. After some looking I found one bolt laying on top of the mower deck and the other had gone to the land of lost bolts.
I searched around in an old canning jar and found that little bolt on the right side that was missing. Looks pretty factory I think. The other one I just screwed it into the nearest empty spot.
I think Dad would be proud but Uncle Harold might shake his head at that one bolt but it’s all I had.