What does the housing bore measure? Have it taken to the big number. If you're using Clevite H bearings, you can realistically get away with going a few tenths over the big number and still have plenty of bearings crush.
Again, as stated earlier, X bearings will give you more clearance, 1s will take it away. You can also save yourself some time by getting a bearing micrometer and measuring the thickness prior to installing.
Not the cheapest route, but if you build a lot of engines, it's a worthwhile investment.
I usually like to hone the main housing to the big number just for this reason. It's easier to take clearance away (in most cases) than it is to gain it.