I like to work smart, not hard.
siphon it into the trans.
put the bucket up on the fender. Might want to put a piece of cardboard on the fender under the bucket, or whatever you have (blanket, etc). Keeps from scratching it.
go cut your neighbor's garden hose, you need about 5 foot of it. 5/8 or 3/4 doesn't matter, 3/4 is a little tougher fit but it siphons a lot faster. Cut the end at an angle, maybe 30-45 degrees. Put that end into the bucket, other end into the tractors' fill hole. Now stuff a rag around the hose, beteween the hose and the bucket's nipple. Now stuff an air blow gun kinda down around the rag, blow a little pressure into the bucket and your siphon starts. Once it's started you don't need no more air....in other words, don't blow the bucket up! Go to the fridge (you have one in the shop or barn, right?????), grab a bottle of water, walk back over after having a swig, feed the shop cat or pet the shop dog..... takes about 5 minutes or so to siphon the entire contents of the bucket into the transmission. Repeat as needed with second bucket.
I'd liked to have one of those service station type dispensers but the boss lied to us about those too, so we had buckets like everybody else does. Learned real quick to find the easy way after dumping 40-50 gallons of oil into transmissions in a days' time.