I thought I'd share a little more of what I've been up to on this... I followed the advice John and Bob gave in the previous couple posts and did a little more experimenting. This meant buying a few more speakers to test, and baffles, putting them in the tender with the shell on top, and seeing what I thought of them compared to the RS Commander speaker and baffle (which does indeed improve the sound) even if it's a little too big for this project. Overall the baffle didn't seem to make too much difference with the oval speaker I was leaning toward previously. I think the one I'm going to go with is the same as Bob recommended though it isn't Sountraxx brand - but is 27mm diameter with baffle and looks like it's probably the same speaker. The most interesting speaker I tested, and probably my second place choice was one from Scale Sound Systems. The speaker was one from their "Full Force Range" of Steam Series Speakers.
After settling on a speaker I turned my attention to the tender frame. I wanted to get rid of the raised lip where the original speaker attached to, the mounting lugs for the original TAS boards, and fully flatten out the area in front of the speaker. I did this with an endmill in my drill press and also located and drilled the mounting hole for the Cruise Commander. The result is shown in the pictures below.
In the midst of all this I kept trying to figure out how to get the light out of the headlight on the engine since I wanted to swap that out too. I didn't care for the colored LED and for my taste would rather have a warm white LED instead. Eventually I figured out that the headlight on these engines is simply a press fit on top of the smokebox - gently pressing up on the hood over the lens will pop it loose. This also exposes the screw that holds the smokebox front in place which will make it easier to work in that area and verify the smoke unit is properly aligned after it goes back in.
