Well, you know I mentioned I needed some brackets for the back to fit the hose's properly and I was trying to get them from vauxhall. Well you cant. They have been deleted and now they send out the two flexi hoses, the solid pipe and the brackets as one big piece thats all crimped together like in evocarlos's pictures. This happened around 2002, so if you've got a pre 02 plate astra you should be ok, but after that your only option is to get down to the scrap yard and take the brackets of an old rear disc astra.
Anyway, I got them on and to be honest the rears didnt make that much difference after all that. I put the fronts on when I upgraded to 308mm discs so it was hard to quantify what good they did. 308mm discs make a nice upgrade though!