I highly doubt you’re going to need the fan. I’ve got two installed; one in a Climax, one in a 45-ton diesel. Neither board gets remotely hot, and that’s driving two motors.
As for the sounds, I’ve played with the balance to make the whistles and bells sound like they’re coming from the appropriate places; fun to do, but from more than 10’ away, or heard from any direction other than broadside, you can’t really tell. It is a cool effect, mind you–and with the 2-8-0 having a beefy boiler, you can probably fit a decent-sized speaker in there and really give the forward speaker some presence. With my Climax, I’ve got a 2.5" speaker in the bunker, but only a 1.25" wafer speaker in the boiler. It sounds good, but because the wafer speaker’s sound lacks base, the chuff is evenly split between the bunker and boiler speaker. It sounds like the chuff is coming from the firebox. Not ideal, but it’s at least got some decent bass to it that way. And–again–you can’t tell unless you’re standing right next to it. My 45-tonner installation uses two 2" speakers placed at the end of either hood. Most sounds are split even between the two channels, but the bell and whistle are on oppposite ends of the loco, so the bell is panned (almost) to one end–“almost” because it’s still a touch behind the speaker, and the whistle is panned to the other end. All other sounds in on that loco are split even.
Later,
K