Bad brain Steve, Just a good jab at my friend Zig and concern for his well-being, but with my understanding that the aluminum pressure valves have been known to have issues. Perhaps his leak is due to tightening too much and causing galling of threads? Either way, I learned that brake lines and fittings do not take sealant if done correctly, so there may be an issue there that is a little bit greater than a leak. No malice aforethought. Andy
Whew..., OK, I guess I can stop worrying. Thanks, Andy for clearing that up. I think everyone here is sometimes worried about Zig's safety. Zig, in light of that concern for safety, I hate to be "that guy", but, I think you might need to re-think your mounting of your pressure valves. In John's link, it says to mount the valves as close to the master cylinder as possible. That is where I have always seen them. In your pictures, they appear to be at the wheel end. I don't believe that is where you want them. I think Russ pictured some in one of his how-to threads, mounted right under the master cylinder. You might want to check into it.
When dealing with a tapered thread.. NPT ..the seal is created in the threads, sealant is fine here. On the other hand, any flared fitting is a straight thread and the seal is in the flare itself, sealant will not help here. I run sealant on NPT "National Pipe Thread" at 2500 psi in hydraulics all the time.
This is a done deal. Tapered thread. worked great, no more leaks. Finally, time to move on with other things.