I'm just about done installing a 912UL into my KF2. I had to rework the exhaust fairly extensively and not I'm making the firewall. The 582 had large openings for the rudder pedals but my exhaust is far enough back that I can maybe go forward an inch and even then the exhaust will be quite close to the firewall. Is there a minimum allowable distance between the firewall and exhaust headers?

I can reshape the headers but I would really like to leave them where they are now. I also worry that the rudder pedals might need to be far enough back that I might be a little cramped.