The FS' cats all hate me.
They all run away/kick me/paw me off when I try to stroke their
backs. 

they're feline predators... so a different tactic is needed..
if they do not accept you immediately, you have to slowly win
their trust...
don't look them in the eye.. look away from them.. go around
their vicinity but do not look at them.. no sudden movements...
after a while, you can try to tempt them with a treat or
something.. hold it in your hand, while not looking at them...
it may take some time, but if they come towards you, still
without looking them in the eye, make soothing noises or talk to
them in a gentle voice.. let them take the treat out of your
hand... then slowly stroke them gently...
after a while, they'll be all right with you
hopefully...