Where is the transmission dipstick located on a 1997 Volkswagen Cabirolet and how do you add transmission fluid?

When my 1999 VW Passat seemed low on fluid, I discovered the manufacturer's theory it would never need fluid, hence, no dip stick. A dealership wanted $200 to change the fluid, and if it was ever low again, same problem. I dropped the pan and changed the filter, drilled a 7/16 hole in the front of the pan, tapped the hole 1/4 NPT, screwed 1/4 x 2 brass pipe nipple into hole, and installed pan. I then pushed 1/2" x 3' heater hose onto nipple, clamped it and brought the end up to hood level. I put in 5 quts. Pennzoil Muti-Vehicle ATF. That was one year/15000 miles ago- no problems.