I'm nearly 61 ... been playing since 67 too. But as I've aged, my voice doesn't go as high as it used to. Some people seem to have a natural gift for harmony, I think it's like that for me. I know the harmonizers are popular but like anything else, they ain't for everyone.I've had no problem singing harmony in the band, and using the harmonizer to add additional harmonies to my sung harmony.
RustyAxe, I started in a band in 1967. We did 4 part harmonies back then and worked hard at them. I've had a good sense of harmony since I was 14. In all the bands I have been in, I listen to what harmonies are missing, and sing those.
At 62 I find it not as natural as it was 20 years ago, but it's still not hard.