Hi mate I haven't done these for years so pretty much whatever info is on the forum is all I know without going back through it.
It looks from here that there's no pins at the relays for the heated screen
relays r2 and r6 i think. Also the electric windows fuse is missing its second pin but can easily be retrofitted but the hard part is splitting the fusebox.
You'll need to find the posts I put up for adding heated screen with pics. It's from 7+ years ago
56 350 2.2 130ps mk7 with 2 side doors
65 290 2.2 125ps custom with 2 side doors
07 350 170ps
Ids v86 licence + v86.04 update + xprog
hereIds map
here