Only photo is at thumbnail in op. I put about 1.5 gal. Of ISO 32 Valvoline “part 700” fluid in and got the level about 4” below top of fill tube. Now runs a bit quieter than before. Agree on overfilling, not worried there. I looked all over inside the big access door, did not find any gauge glass or dipstick, probably because the exact level isn’t critical and is probably described in terms of “inches below...” in that elusive service manual. If photo of the actual mo-sheen would be of interest I can slap one or two up there. I bought it used but has been a great help in crowded warehouse, more versatile than our Hyster S60 propane forklift. Another advantage is no starting/warmup time needed, it is instantly on when you turn the key. We were lucky and the battery that was in it seems to have a lot of life remaining even though we charge it with a smaller charger than one with the recommended AH capacity.