Missing Oil Dipstick and Associated Parts

Wow, one I haven't seen before. On our 71 Demon 340, there is no sign of an oil dipstick, or the tube assembly, or for that matter any sign of where that would even be installed. The engine was rebuilt 2 years ago, and it runs great. It has been driven sparingly since the restoration phase, and still working some bugs out. Thought I would check the oil (it was changed about 6 months ago, garage never mentioned the lack of a dipstick) and not a sign of how to check it! The oil pan shows blue beneath the orange paint. Not sure if the pan was replaced with no thought of reinstalling the dipstick parts...very strange....pics would be appreciated, and I might be looking for a correct oil pan with hardware I'm thinking!

Thanks,

Mark