Just incase anyone else comes across this thread in a similar situation:
It tore when I was trying tease the memory out without it ripping, installed it as normal, and everything seems fine, looks like it is just there to stop dust or something.
So to sum much doesn't matter if it rips.
I believe this was the first time the memory had been changed (had 1GB to start with, with a brand apple uses), the bloke who owns it says it was it storage a while might have happened, first time i'd touched it in any case.