DOn;t think the Soubndcar would come close to fitting in the N scale cab cars, which have full interiors in them. They do have a space for a speaker, but the Soundcar is a fairly large decoder.
Check with Atlas - I think there is a specific ESU decoder for these that is a direct board replacement. Atlas doesn't seem to document things very well, all the information in the information section is mainly for older models - even the quick start included in my brand new RS-3 is one printed for a Loksound V4 decoder which the previous release used, mine has a Loksound V5 - the huge difference being the CV to set the horn type is completely different. Calling them or emailing them may get the information on just which decoder they recommend for the cab car.
Other Atlas N scale type decoders may also work. Control of the lights in the desired fashion is no big deal, standard functionality on nearly any decoder.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Any "function only" decoder will provide basic forward/reverse lighting functions for a cab car.
This decoder;
https://soundtraxx.com/products/tsunami-soundcar will provide lighting plus horn sound - just forget the animal sounds!
As with any decoder, check it will fit - does your cab car have electrical pick-up from the trucks?
Trevor
Doers anyone know if there's a decoder for these cars to operate the lights on DCC so they're white in push mode and red in pull mode?
The N scale section of my website is now uploaded with a lot of various things. Check it out: www.CarlettaTrains.com