When most people go off-roading they mean woods, desert, stream beds wet or
dry, and other such social ecological interaction.  When I take my Doka
off-roading I mean driving down the shoulder or median of the highway,
possibly pulling into empty construction areas.  This is where the flashing
light question comes in, or on.
Two things that really bother drivers in my area: driving whilst on the cell
phone and those printed graffiti road sign advertisements.  Now in VA it is
illegal to put those signs on the "public access", but equally illegal for
the average citizen to remove the illegal signs as well.  My solution was to
join VDOT Adopt-A-Highway program so I can remove trash and signs where I
find them legally.  It's a good walk and I can drive my truck about my area
looking Cool and doing some social good.  As an aside, I have found a Bosh
cordless drill in its case, a Dewalt saw in its case, a dollar, and the fact
that at my age I can still get a fractured clavicle (but that's another
story).
Back to the question.  Remember this was about a flashing light question?  I
want to install a light mounted on a post that will go on when I turn on my
flashers.  Buying a flashing light unit means the thing will flash
internally, which will conflict with my emergency flashers if I add it to
the circuit.  SO, how do I, or what do I get, to make up a flashing light
module I can put on my truck when needed and tap it into the flashing tail
lights?
Ed- just call me The Flash