That's one of the options I was looking at by filling the whole void with JB Weld then milling it flat and carving out the inlet path... If I use JB to fill areas like this I'll throw in some chopped fiberglass strands to make a Kitty hair bondo type solution, but with the jb weld. I've repaired a radiator that way where the top hose nipple cracked and I knew JB by it's self probably wouldn't have held until I had time to take the radiator out to solder it and fix it right... Anyway, a week went by and this held just fine, but I took the radiator off to do the repair right and couldn't get this stuff off so I painted it and put it back in my 4x4 blazer where it lived that way for 3 years of very rough use until I sold the truck. So JB + chopped fiberglass strands makes for some bulletproof composite parts.
For mounting, my plan is to drill thru the cases and countersink the holes from the inside and use countersunk screws from the inside and nuts on the outside, the screws will stay put by using locktite, of course, if I use the JB weld and fiberglass trick, the JB will keep the screws from backing out or falling out during assembly or disassembly. Also need to remember to use a sheet of teflon between the case halves if made from the jb weld and fiberglass so we don't bond the cases together and have to cut the split line after the cure.
I was able to successfully make me a set of bolt on stuffing plates like I mentioned before, the bolts on the outside of the case are barely noticeable but still looks cool, and I'll still glue them into place with JB weld just to be sure they can't move as there's only .010" clearance between the plates and the flywheels now, thrust washers are also mandatory for this case now.
