I've used something like this for years over 5. Made it from a stainless steel tray drilled holes for my ink caps and water welded to a music stand.. One side for bng the other side for colour. Great if you don't kick it then it good by ink...Water. but it does make life alot easier no turning and when you had two major back opps I want everything without the turning. I'm at mark 3 now which I'm very pleased with the lay out I use.. but a using carbon is nice but it's porous, were the cut holes are, the resin only penatrats so far into the weave, even if it's been autoclaved with prepreg, water or ink or anything of that matter will lay in the cut...the only way is to make the plate with the holes all ready in the mold. Why I know this is (a) I've worked with carbon for years (b) a family members work in carbon for f1 teams. Plus ive made a top plate in carbon mix and you could see the ink stain the holes where it was cut...i have to cover it with cling film and push the ink caps though it to seal the ink cap in the hole..The only way is have the top stainless and removable and that is going to be my mark 4, now I've finalised my holes I need.
Good luck with it.