If the ATF filler bolt is not occupied by a 2nd gear oil jet modification then you have the option of refilling the transmission through the ATF filler hole.

I decided not to do this because:

1. The filler bolt is very - very hard to remove.
2. I found it a pain to refill without spilling fluid with the filler plug down so low.
3. A refilling jig used to fill through the dip stick tube is so easy, it just takes time.

This is just a plastic bottle with a hole drilled in the bottom side that is slightly smaller than the clear plastic tube.

I used about 1.5m of larger plastic tube for most of the length and then added a smaller diameter piece of tubing that fits easily into the transmission dip stick tube.
You only need to insert the tubing about 50mm (2 inches) into the transmission dip stick tube.

The hole in the lid allows air to enter as the oil is drained and is a convenient place to push the end of the filling tube when not in use.

I use a lid in case the bottle is knocked over during refilling. It takes about 15 minutes to refill three litres. Go away and do something while it refills.