Okay gang, I have been reading all the post about the ballast upgrade projects and have learned a ton of stuff. I am almost ready to plumb in a proper ballast system into my 2001 Outback DD. I am planning on using areator pumps (Tsunamis), but I am having trouble figuring one thing out. The bronze thru hulls are NPS threads, yet the ball valves that most people seem to use above them all seem to be NPT threads. Then it looks like the standard Tsunami pumps are NPS threads again. How did you guys deal with this?