Replace with this

I would replace the factory board with this board from Soundtraxx.

http://www.soundtraxx.com/dsd/tsunami2/products/tsuPNP.php

Easy job and should fit.  Add your own speaker/speakers and program it for the Alco 244 sound file.

Soundtrack 885015

Thanks Nelson. Like the current keeper availability. Measured. Appears to be good fit.

Huge flexibility

These new Tsunami II boards have huge flexibility in mounting and now with 6 output functions give one the ability to set up ditch lights to flash and still have 2 outputs left for other lighting.  Cab and step lights can now be added or strobes and such.