Mine has two flasher units; one under the dash for the headlights and one in that electrical panel behind the driver's seat for the flashing lights on the module itself. It also had a strobe pack which controlled the strobe lights in both the front and back rear light-bars (different from yours, I think), as well as the strobes on the two front fenders.
As far as a couch/bed goes, I'm thing about using something like this. It's made for RVs ($$$) and the seat pulls out to make a full size (?) bed. As an option, you can get it with a drawer underneath for storage. The problem is, would it fit over the wheel well even if the existing box was removed, sacrificing all of the storage space. Maybe, just use the top couch part without the base somehow?
http://www.discountvantruck.com/rvsofabeds/motorhomefurnituresofassedona-I.htm
I'll take some pictures of my panels and post them up. Theres a couple of "flasher" thingies in there, and I remember one specifically labled for the headlights.
I looked at those rv couches as well. Besides the price, when folded flat they dont make all that good a sleeping surface, kind of lumpy. That plus the fact that I haven't found one yet that isn't a horrendously overpriced piece of home made crap. Seriously. I havent found anything in the rv industry that isnt absolute junk, which given the cost should be criminal.
The rv industry, at least for the folks that arent buying the hand built one-at-a-time multi million dollar land yachts, is a total joke. It's all about skin deep beauty, and that's where it stops. Like swapping a corvette body on to a corvair chassis, with 200 k already on it. I have a 43' fifth wheel toy hauler that looks great. Pull some panels here and there for maintenance/repair purposes and it takes about 1 look to realize what poorly constructed pieces of junk they really are. Been to the factories to watch construction. Git 'r done, an out the door is the mantra.
Ok. Sorry....all better now.
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. Anything Rv gets me a little worked. You look at the electrical panels in your ambulance and just understand you will never ever see anything even remotely professional as that in your standard rv.
Back to.....
Someplace in here is a thread where someone did exactly as your thinking, but they ran into clearance issues with the wall when laying the bed out, so they had to mount it to a sliding platfrom. Pull platform out, lay down bed. Put bed up, slide platform back to wall. I dont recall what they ended up with as far as storage goes. Given the design I'm guessing not much.
I'm liking my fold flat seats idea. Pretty sure I'll lose any storage capacity under them, but I should still have something left in between. Think a big square center console kind of arrangement.. Could even put some cup holders in there. Also got an idea for mounting a table in front, that wont take up any space when its stored. Much to do, not enough time to go around, and too stinkin cold! Talk about a motivation sapper.