that all sounds good to me BE but i am suprised your buying a cpu block i though you would have something made.
here are some pics of an impingment block i made today it's very rough just so i can see what i could do. I made this in about 3 hours again from an akasa base.
i even managed to cut the area around the jets like cathar but it's not even close by 1000000000 miles to cathars block what fantastic work he makes.The dimples are 1mm above the cpu core.
it's made for p4 again. i have it sitting waiting for the silicon to set then i will test it againts the maze 3 soon.