bushing lifter bores on 340

It is an R3 block but the procedure would be the same for any block that had its lifter bores bushed.

If your machine shop were agreeable, they could even drill the holes before they pressed in the bushings....that's a lot easier. But it does require them the press them in with the hole at 6 o'clock and at the desired depth.

With a bronze bushing, you wouldn't be able to drill an 1/8" recess, though, because the wall thickness is too small. You'd just drill the small .046" (or whatever) hole.