Thanks for the response, Manny, but I was not looking to compensate for the tendency to drift right - just to correct it. My experience with previous vehicles is that when the chassis is properly aligned, any effect of crowned roads is very slight, if at all, in directional movement. I guess my question is whether the previous alignment might have compensated for uneven wear, and now needs to be redone to 'de-compensate'.
I had hoped stevebfl might have contributed some helpful comments specific to my problem, but he has apparently headed elsewhere. Perhaps someone else who does alignments will be willing to share?