The obvious question is.. Why?
I like the caveat.. „Disclaimer: This is a highly-advanced hack! Do not attempt it unless you have great confidence in your metalworking and mechanical ability. This article assumes that you are already very familiar with the inner workings of Sturmey-Archer AW 3-speed hubs. If you have any questions that you can’t figure out the answer to from this article, you’re not ready for this!“
I began riding, as many did, years ago on a Raleigh Chopper and a Raleigh Commando (my brother had the Grifter) which had the classic 3 speed Sturmey Archer setup. It had a little oil grommet through which you could top up the oil in the hub. It meant the hub got quite oily and picked up dirt easily. Difficult to clean. Can you believe the Chopper has an owners club! Crikey.