I started work fitting the washer system yesterday. I couldn't use the washer bottle kit I got from CBS at Stoneliegh, as the only place it'd fit was directly above the exhaust... I didn't fancy having to clean melted plastic from the pipes.
I've followed Robin's lead, and used a Alu water bottle from Millets (£3!) - but I have mounted mine horizontally in a cradle on top of the scuttle above the pedal box.
I've bonded a spigot into the cap and drilled a small hole on the shoulder of the bottle to allow air in as the water is pumped out. There's a dip tube inside on the other end of the spigot, which I've weighted down with some stainless washers to ensure it staus on the bottom.
To fill it, I take it out of the cradle, spin the bottle to get the lid off and then pour the fluid in. Spin the lid back on, and lay it back in the cradle with the vent hole facing up. Simples.
Just waiting on some nyon webbing and some adjustable plastic clips (like on rucksacks) to arrive to secure the bottle in the cradle.
I also need a decent one way valve... the one I got from halfrauds was a non-way valve. I could barely get it to open by blowing through it... :/
I'll get some piccies later on.