Oh yeah, I forgot some kits have to flip it due to output shaft rotation, sorry. Guess I was maybe thinking GL1500s & Valkyries, but yeah,yours is a VTX (but you knew that). I know it works to correct the rotation (so as to not have 5 speed reverse and no forward gears), but I do wonder how well the pinion shaft bearings get lubed. I guess that a drain & specific volume refill is the only way to "know" then. Maybe after doing a refill that you know is right, be a good time to make yourself a gage to "stick the level" via fill plug hole, something you can stick in and see a lube level on?I am aware that there is a plug, and it is the level for when the rearend is right side up.
I read else where that when the rear is 'flipped' or inverted, you cant use that anymore because it is too high. It was mentioned that the rearend needed to be drained, then filled with a specific volume, with that volume usually available from the manufacturer.