priming the oil pump

You may have to take the head bolt out to get the wire to go down into the passage in the block. I had to do that while doing this very thing with my 273 a while back. It won't hurt a thing to take the head bolt out to run the wire down by hand. Just retorque it when you're done. If you send the wire down the hole to where it obviously stops at the cam, rotate the motor by hand and you will feel the wire drop like a rock when the oil hole in the cam lines up. I got worried because my cam was made on a Magnum blank. I called Bullet and they assured me that it had oil holes like an LA cam, but I wasn't gonna sleep good until I checked it myself. If you get the wire down farther after removing the head bolt and it doesn't drop into the cam oil hole after you rotate it, that cam bearing may be installed wrong.