Swung by Airparts and picked up some scat tube and band clamps. Once I got home, I mocked up the scat routing with leftover hose from the cabin vent installation because it's the same 2" diameter. I then ran a bead of RTV down the length of the scat sections to keep the exterior thread from unraveling. For future reference, my scat sections ended up being about 16" and 40" While I was waiting for the RTV to dry, I moved ahead to installing the magneto blast tubes. Nothing special here. Took about an hour of playing with it to figure out the best routing with the least interference with other stuff. Had to move a couple of adel clamps, but no big deal. Back to the scat tubes. Conventional wisdom says that with this type of heat muff, you typically get better heat transfer if your cold air in is further downstream on the exhaust with the air out to the cabin port upstream closer to the exhaust valve. In my case the position of the muff, all the stuff around it and the scat routing I'm using made it work out a lot neater to go the other way, so we'll see how that works out. I built a band clamp out of .020 aluminum shim stock that you can see in the pictures below. It's secured to a high temp chemical resistant Adel clamp at the intake pipe for cylinder 3. Other that that, the entire scat run is just stuck with red RTV anywhere it might chafe. By careful positioning, it's secured where it shouldn't rub anywhere, and has about an inch minimum of clearance in every direction where it threads through the engine mount. The only potential interference I have anywhere is where it touches the end of the dogleg brace coming off the alternator. Once the alternator is on and tensioned I can put a dab of RTV on there if it's rubbing. Alternately, I think Vans has a metal elbow that will fit the heater muff. I might get a couple of those which would allow me to shorten up both these scat tubes a bit and clock the fwd one differently to get it away from that alternator bracket entirely.