Having had problems filling all of the above I made a simple device that can be used for all of the above. All you need is a old fizzy drink bottle and clear plastic tube. Just drill a hole in fizzy bottle top slightly smaller than the tube, force the tube through the hole and make sure it reaches the bottom of the bottle. Most fizzy bottles use the same tops, so this can be used with 250ml bottles up to 2l bottles. Just fill bottle, insert tube into gearbox etc squeeze bottle to transfer contents. Easier and less messy than inverting the standard bottles. This can also be used in reverse just pull the tube up so it's just below the top, squeeze, insert and let go to retrieve fluid.