Seems like only yesterday I was asking the same thing on here.
Yeah WC has it really. What I do is go tesco get a cheap spray bottle something like windowlene and then empty it out and fill with GG4 and water. Or use deionised water its like 17p a litre and its in the car section at tesco.
Spray on, clean, and then buff up. That how to get a serious shine on lead
Looks good if in a couple days you go back and check as lead are a pain and you dont know whats bee on the frames and glass before, some people do some strange things when cleaning there own windows.
I have a couple were the lead is sooooooo old I cant use any liquid and just have to dry cloth them. Makes a mess of about 10 micro fibres but the custy pays