I put warning beepers, the backup alarm type, on my L4310HST. I put one of them on the front, on the loader grill guard, and one on the rear beside the fender. I hooked them up to an On-Off-On toggle switch - flip the switch forward and the front one came on, to the rear for the rear one. Full details, with pictures, are in the "L4310 enhancements" thread in "Customization". If you need any more info, let me know. Horns would be different, in that you would need a relay for each horn (though maybe you'd only want one, or only one relay and switch which would blow both front and rear at the same time), and a momentary contact switch instead of toggle type.
My EF-5 has horns front and rear with a pushbutton on the shuttle shift lever and a pushbutton one on the rear backhoe control panel. I can take pictures of it, if you want, but I don't know if it would be very useful to you. You make the call.