Lol I had the same problem mate. I labeled everything up with masking tape with corresponding numbers but some I did in ball point pen which faded
For the cooling I totally had to re-customize the system as the polo radiator had 1 less connection than the sierra did. I added an additional T piece to the bottom rad hose that goes into the bottom of the block and the hose that comes out of the bottom of the header goes into that. Here's a thread I started awhile back when I was on this part, hope it helps!
http://www.haynes.co.uk/forums/showthread.php?t=6873