When is it necassary? I have a good 4 bolt main 350 block that I would like to build up but is has rusted from sitting. I'm planning on honing the lifter bores to remove rust and having the cyls bored .30. Question is, should I have the crank journals line bored or just honed? Should I be concerned about the rust? The block wil be going for cleaning and boring but I will have to ship it away for the line boring and I don't want to do that.