How/Where do i change transmission oil on a 72 VW bus?

it's an automatic transmission. there's a slight leak, so i'd like to add some fluid myself occasionally instead of waiting until last minute and paying a mechanic.How/Where do i change transmission oil on a 72 VW bus?
As with all automatics, it goes down the dipstick tube hole. Pull the dipstick out and with a long narrow funnel pour in the fluid. Take care not to overfill it. Put some in and wait a half hour , pull the stick, wipe off and try it. I know it is like pulling teeth. but the additional fluid may still be in the tube and it will mess up the reading as it smears all over the stick.How/Where do i change transmission oil on a 72 VW bus?
not sure about the bus but on the beetle (72) on the driver side there is a hex wrench stud on the transaxel about mid way down the trany that needs to be removed to check and add the oil.i do know to NOT OVERFILL IT. IT will BLOW the main seal and leak horribly. it leaks now probabley becouse the seal at the CV joint is bad.its easy to fix.
Gotta pull the pan....