If you make more please put me down for one (maybe two), my guess is it will work nicely. Also, thank you very much for the picture - now I know what it's supposed to look like.
>I think I can get more of the correct copper crush washers so that the bolts don't leak.
Copper crush washer you say? The existing washers are steel with rubber gaskets, and judging by the amount of sealant that was used the previous owner had a problem getting a good seal. Any chance these would work?
> I replaced all of my water manifold bolts with stainless ones, put copper Never-Seize on the threads.
Seems like a fine idea since they are going to be in contact with the coolant.
Background, in case you are interested:
I bought the car at auction about a month ago. The car overheats after driving it for ~10 miles. Here is what my manifold looks like.
Someone cutout rectangular sections, and then welded back in a stainless steel ruler (you can see the ruler markings in this picture).
I found the thermostat in the trunk (literally). My guess is the car was overheating so the previous owner removed the thermostat and cut holes in the interior plate to try to address it. Maybe it didn't work and they welded the ruler to block the holes? Call it a working theory.
I'm going to make sure the thermostat is in working order and put it back. Cleanup the manifold and (if you make more) replace the internal plate/baffle. Flush it a few more times. I've flushed it a few times (the fluid was not healthy), and with the manifold off I can see it's not enough. Probably use an additive to remove rust. Seems like maybe taking the water pump apart and looking at it would be worthwhile too.