I just had my Boily SI3600 stolen from the back of my truck. It sat forward of the 5th wheel hitch, weighed 75 lbs, and was chained to the hitch with a high security motorcycle anti-theft chain. I think someone dissembled one of the lifting bars (which I had beefed up with steel pipes and JB Weld in the socket head screws holding it) The intact chain was left in place through the 5th wheel hitch. There is a picture of it here:
http://boliygenerator.com/
What ticked me off the most is that the thieves had to do a fair amount moving and walking around in the truck bed and no alarm sounded. I plan to upgrade my truck alarm system.
Meanwhile I didn't want to be without a generator, and have changed my philosophy to "If I need Air Conditioning, I check into an RV park". So I found a quiet, efficient, 2500/2200 watt inverter generator from ETQ. Here is a link:
http://www.ebay.com/itm/170963854066?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 . THIS time I recorded the serial number, and got out my soldering iron/black marker and used it to mark the plastic case with my California Drivers License Number (that has gotten a stolen tool box returned to me before). Unfortunately, where I had the old one in the truck is the best place to keep the new one. Maybe the bad guys won't cut through the heavy handle molded into the case halves to get the chain off, my CDL markings will deter them, and 1 or more alarms will scare them off, along with me getting a cover for the truck bed to keep things out of sight.
BTW, I found I could prop up the 5th wheel hitch flat with a prop stick under the hitch plate and a bungee cord stretching over it pulling down. That way I can use a canvas cover I plan to get from McMaster-Carr.