There are a million ways to go on this one. One way which is very cost effective and will let you get things just the way you want is to simply take your measurements for your tunnel extension and go to your local Heating and Airconditioning shop and they should be able to bend one up for you for under 50 bucks out of aluminum. Just make a diagram of what you want, they should be able to roll the edges too.
As far as the rails go, either buy Powder Special rails which will set you back about $100 a piece or get rail extensions. HRP or Holtz should have them. One other thing you can do if you are setting your ZR up for mountain riding is remount your 121" rails back further the tunnel to make up the difference in track length. You will have to relocate or fabricate new suspension mounting plates. I have done this and it is great because you create a much better approach angle for the track in the deep snow. But, thats a whole different story.
Tell us what you are converting your ZR to longtrack for and the route you take will be different depending on the intended purpose. What size lugs are you talking about? 1", 1.25" or what?
As far as the rails go, either buy Powder Special rails which will set you back about $100 a piece or get rail extensions. HRP or Holtz should have them. One other thing you can do if you are setting your ZR up for mountain riding is remount your 121" rails back further the tunnel to make up the difference in track length. You will have to relocate or fabricate new suspension mounting plates. I have done this and it is great because you create a much better approach angle for the track in the deep snow. But, thats a whole different story.
Tell us what you are converting your ZR to longtrack for and the route you take will be different depending on the intended purpose. What size lugs are you talking about? 1", 1.25" or what?
