I do not solder or use o-ring... there can only be GOOP
well none of my customers are morons

so I'm not worried about them screwing up something like that...
I am however taking care of that possibility that the two halves might miss- align, by being very precise in my drilling... the holes align perfectly, and since the bolts are counter-sunk, they re-center the top block as you tighten them... Works really good actually..
a milling machine would indeed be very preferable to actually be ably to have each hole overlap, with the next, and in doing so, nullify the need for all the Dremelling... why you wana donate me a mill? Maybe?? Maybe?
I dono.... the links on the first post seem to be in perfect order...
can not see why they would not work....
MDM your idea sound prety close to what I had going in that rendered picture of the block...