First experience messing with hydraulics yesterday. My Kubota 2410 compact tractor sprang a hydraulic leak on one of the lines that powers the bucket. All four lines were the same age, so figured it would be best to replace them all. One trip to the local Kubota dealer and $111 later (9 feet of 3/8", with the correct male and female fittings on each end), spiffy new hoses. Had to transfer the old quick releases from the old lines to the new lines at home. What a pain that was. Had to clamp the line in my vise at the fitting so I could get a wrench on each end of the fitting to get the old ones off. They were pretty darn tight, and that was yanking on them with a 3/4" wrench. Plus, the tractor was at our rental property that's a few hundred yards away from my garage with the vice. And of course, had to make three walking trips back and forth for tools and vice usage.
Then topped off the fluid. It lost around 1/2 quart, give or take. The fill spot is under the seat and requires a long slender funnel. All I had was a five gallon bucket of hyd fluid. So, I did what all shade tree mechanics do and used my fluid transfer device, otherwise known as a huge turkey baster.
I've used it in the past for empty brake fluid reservoir when bleeding brakes, or other delicate type operations. This is a BIG baster, guessing it holds around an ounce of fluid in the bulb. Took 16 bulbs worth to get back to full on the dipstick.
This is a pretty close version of what I have. Stainless steel and all. LOL
https://www.amazon.com/Norpro-Deluxe-Stainless-Injector-Cleaning/dp/B0000CFTOE