Hmm, wasn't a great success.
The last tweak, all be only 0.2mm, was a tweak too far and the part wouldn't fit the drum properly. Too much force split it but it wedged in sufficiently to give it a try.
The theory works well, no glugging and the oil comes out so fast that I think a spout and possibly a restrictor would be an advantage.
Looking like the Rawplug design may have to be investigated ... back to the keyboard as they never used to say.