Mmmm . That does sound nice - quite quiet, yes? What shape are the bottom exhaust mounts (1 & 3) - notice you've got j-tubes? Will they clamp up onto standard heat exchangers with usual horse-shoe clamps?
They will snotty, but you can also get a flange to weld to you HX's so you can do away with the pesky clamps and bolt it up properly.
