my first 742 case rebuild, need alittle advice please

I was told by an old diff guy that if u can't get the pattern right on the drive side that to get the best pattern on the coast side. He said dont even be conserned with the drive side. He said some used gears can be a bear. He has set used gears up on the coast side many times. He did also say the more than likely u will have a whine. Kim.
I agree,that is what Yukon gears advises, Used gears, look for a good pattern on the coast side only.