The F150store.com just went "live" with their web site and I saw this ... figured I'd come back and post:

http://www.f150store.com/Shop/ViewPr...&PlateTypeID=1

 

my bro did some research back when he wanted a loud horn. didnt wanna use up the bed for a big compressor, and there was nowhere he could mount something big enough to power a train horn. but if you dont mind using the bed, then go for it. just be careful, could really damage peoples ears with that.