Help guys..

I just did a valve adjustment and bought new spark plug seals/gaskets since i was removing the valve cover. I'm in the middle of it right now and i can't get my valve cover back on until i can replace the spark plug seals. I tore two of them already trying to remove the old ones. They seem to be fused to the valve cover...i'm trying to scrape the rest of hte rubber off and out of the grooves so i can put the new ones in but it's taking forever (over 1 hour so far and still haven't gotten one out yet). Any tips? anyone else have this problem before?