I am working on an Aristo 2-8-8-2 mallet, converting it to live steam using the running gear from two Aristo Mikados. I am building a custom boiler for this loco. I have to have flexible steam and exhaust lines for the articulation. I havent seen how Aster did this or Accucraft on their cab forward. Any suggestions, photos, on materials, designs, on the lines, or articulation methods would be appriciated. Aristo uses a center pivot point between the second and third drivers on both sets of running gear. This is obviously the easiest way to do it, but the prototype had the rear set rigid to the frame while the front set was the only articulated part. So i can either articulate both sets, the easiest way, or I need to make some working mechanism to articulate the front set only. Any ideas on that would be appriciated also. I will post a thread on the build after I make more progress. I have been taking pictures and plan to insulate the loco simular to the way Aristo did to the mike. Any suggestions out there?