arcing plugwires

Hello everybody.I'm new to the forum.My question is i have a 1994 s-15 4x4 vortec 4.3.I replaced the coil,plugs,wires,dist cap,rotor,ignition module but i keep getting a arc from my plug wires-(new sets don't help)the thing runs rough and eats plugwires-any help would be appreciated.

Thanks for the help?But it was the oil sending unit grounding-(it's 1/2 from the dist.