Car insurance, like homeowners insurance, has some coverage latitude with regards to personal possessions. It is easy to get something as straightforward as running boards, headache racks, rear bumpers, fender flares (things that bolt on) covered. Same applies to stereo equipment as it usually is 'installed' structurally. Even a brake cntroller or a toolbox bolts on. Then comes those things that 'plug-in' like power boxes, pda's, radar detectors. The real key is receipts and pictures of these items IN the vehicle.
One key to insurance for the first 2-3 years is paying a little extra for 'replacement value'. This keeps you out of the 'depreciation' tables and up front for better insurance claims, especially when theft is involved. They can beat you up over the depreciation in a theft and turn around an talk how well the same vehicle holds up against depreciation when looking at costs to total vrs repairs. Replacement value also holds up against sub-standard aftermarket replacements vrs oem parts where body work from an accident is involved.
Technically if something is bolted on a vehicle, installed with attachments (ty wraps), or in the vehicle when it is stolen it is supposed to be covered. That would even include a brand new TV sitting inside the truck. Things found in the bed that are 'loose' can be argumentative. I have seen guys get paid for the tools in their toolbox as it is considered a 'secure' area.
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