As the posts above acknowledge, the washer bottle is perfect as a recovery/closed system coolant tank:
1) bottom nipple places coolant "head" on line to overflow nipple on tank neck, always keep bottle 1/4 full minimum.
2) 1/4" ID hose is a snug fit on both ends.
3) snap cap vents bottle, drill a small hole if yours doesn't have a one (some repops)
4) ample reservoir capacity for coolant system
5) best of all, it already mounts in the ideal spot!
I run a Totally Auto repop bottle, they make clear/white and yellow/aged versions. Note - I found the small amount of flashing on the bottom nipple from the mold parting line was enough to cause a micro-leak from the hose. A tough leak to chase down, but my suspicions were confirmed. She's liquid tight now..