Sounds like you know what to do, ...get the carbon fibre EPR one then by the sounds of it is the plan.
When I did mine I put masking tape over the bits I was going to cut out and then drew the lines where I wanted to cut in pencil onto the masking tape. I was also able to kind of lay my old pre-cut cover on top of the carbon fibre one to give me the rough lines.
I used Dremel fibreglass reinforced cutting discs as I found they worked the best for cutting the CB.