Connected Battery backwards...ouch!
the thing screwd in the back of a small block v8 is the oil preshure sending unit. wouldn,t hurt it. your just going to have to look at things one at a time.The electronic things possibly could be damedged but not nesesarily.do you have spark. If not check to make shure the modual has power.If it does and you don,t have spark your in trouble.i douwt you would hurt the fuel pump but if its not pumping folow the power path.check fuseable link.good luck