I am trying to make a change to our cooling system. Seawater comes up through a street ell and enters the transmission/engine oil cooler. These two coolers are parallel. The cooling water splits, transits both coolers and comes back together at the other end. The cooler is designed such that the zinc plug is 1/8" and you have to saw off the zinc to about 1/2" long or it will hit the tube bundle. Needless to say, it does not last long. I want to install a 1" cross at the cooler inlet. The cooling water will enter from the bottom, turn 90 degrees, then enter the coolers. On the top of the cross, a bronze plug drilled and tapped for a machine screw where the bonding wire will attach. There is currently no good place to attach a bonding wire. When I open the engine access door, the zinc plug will be right in front of me, easy to access. As long as I verify low electrical resistance from the zinc and bonding connection to the cooler, this arrangement should be OK. Also, the oil coolers and the engine cooler can then both use the same zincs- 3/8" NPT and not have to be sawn off. Problem is, I can't find a bronze close nipple. I'm looking for a source for the cross and nipple to save on shipping. The cross I have found at several places, but no nipple. Does anybody have a source for bronze nipples? I do already have the bushing and plug.