What is the best way to make replacement track guards? I have some sheet brass that I can use but dont know how to go about it. Any tips??

I think you'd have a difficult time with brass because it's so hard. If you use some aluminum or lead sheet you can supposedly use the kit parts as forms to burnish the sheet over, and trim to size. OR I'm pretty sure there are PE ones available.

To use the brass. First, Make a form of the guards out of hardwood. Second, anneal the brass( heat it to red and let it air cool). Third, form the piece over the hardwood plug with many, many light taps of a hammer. Fourth, trim the formed piece to shape. File the edges smooth and your done! Some work, yes. But not all that hard.
capnjock

i found this in the shoping section hope it helps !
http://www.best1hobby.com/html/aber/aber354.html