Two quick thoughts...
We blend fuels by volume. The John Deere lists it has 80% diethyl ether, which appears to be by weight. Ether is lighter than water; its specific gravity (weight compared to volume) is about 0.8. SO... 80% by eight means 100% by volume for our purposes. In our units, 8 ounces (weight) of ether makes 10 fluid ounces of ether. That's almost a third of a quart, close to the % we want!
Second, the JD ether cans have a spray cap. WD-40 cans (usually, at least) use a spray cap with a thin straw. A little experimenting will find a spray cap w/straw that fits the JD can. I 'catch' the ether in the quart mason jars used for canning fruits and vegetables. These have replaceable inner lids.
Punch one inner lid with a hole a bit larger than the straw, and have another lid - or jar - with an intact 'inner' - handy. Chill the jar a bit, and spray the JD in through the hole. The clearance lets propellant, or the ether's vapor pressure, to escape. The chilled glass helps the ether condense to liquid. Capture is pretty darn good. You are using the pressure to get the ether out.
When you've got most of it out, and pressure is gone, there's still some liquid in the can. THIS is the time to punch two (or more) holes in the rim of the can. One hole, of course, to pour out the remainder, the other for a vent. When the can has been really emptied, switch to an intact jar lid to seal against evaporation loss. Of course, don't leave the jar sitting in the sun, or some other 'too warm' place until you blend your batch.
BTW, if you've drawn out enough for a batch, and some remains in the JD can, that's a good place to store it until you need it. A partially emptied can is useful when your blend needs a bit more ether than one can provides.
Safe, with reasonable care. Effective. Little waste or mess. Sensible storage...