Chris...there is a lot of good info here......I have used this procedure for mixing bearings and it never failed me.....
http://www.enginebearings.com/it_bearinginstall.asp
If you will accept a little advice........Bearing clearance is usually safer on the looser end of a set of specs.......0027" to .0032' is a good range for most engines........
You can buy coated bearings in all the sizes they offer or have them coated. The coating reduces your clearance from uncoated and the companies that do the coating can tell you how much per set.....
I have used coated Tri- Armor Clevittes and also had some done by Swain. Calico is another very good company for coating bearings........