I went with the masking tape approach at the 25-35mm range from the bend. Used the metal bar from one of those pants hangers with the two clamps.
It was tough to tell if I was bumping into the sides on the way in, but it seems the tape came out wet. So I think fill might be ok. Although its not 100% level in the garage and I went with driver's side jacked up a little. Used a flashlight in a pretty dark garage so was tough to get a good read while laying on my back and holding the flashlight with my chin.
So... With with 2nd test a pass, that's 50%, which is still an "F" these days, right? I checked the engine oil and it was overfilled... So that's only 1 of 3 right... 33%, an "F-". More fodder for my "chat" tomorrow.
I've had a good dry run for my next DIY NV146 drain/fill.
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