DF175 lower unit oil level plug

[maxthebird]

The slot in the lower unit oil level plug on my df175 is stripped and I need a replacement. The parts diagram shows 2 drain plugs but no oil level plug. I ordered the drain plug thinking it was the same, but it's slightly smaller with a beveled head instead of a flat head. Why isn't it shown on the parts diagram and where can I get the original part?

Thanks

[Harper]

All three plugs are the same, part number 55128-93J00, and they use the same fiber gasket, part number 09168-10034. I've had all three of my plugs off the lower unit at the same time, and had them lying together and never paid the slightest attention to which one went where.