I went through an 85 or 86 police 318 for a 91 truck one time. It had the quadrajet carb with open chamber 360 heads. 345 or something casting number. The pistons were a little closer to the deck than a normal 318. It was a roller cam block with a flat tappet cam in it. I put it in the truck with the TBI and it was a real turd until I put closed chamber heads original to the truck back on it.
Im pretty sure it had never been apart. If i remember correctly the heads had the large push rod holes required for the shorter roller push rods, but like i said it had the regular flat tappet cam. The bosses required for the factory roller lifter hold down deal where present, drilled and tapped.