Jim

Sounds a lot like "seborrheic dermatitis" which is a fancy medical term for itchy scalp with scale deposits. In infants, it is called "cradle cap" which sounds a lot nicer.
I had a very similar problem and what worked well was
Neutrogena's T-Gel therapeutic shampoo. It uses that old fashioned remedy my grandparents used: coal tar but unlike the standard coal tar shampoos it's really gentle.
It was so gross when my wife was cutting my hair (barbers are too expensive with my medical bills) and she would find that scab with the hairs in it that I asked my dermatologist. Since I have been using it, the problem of itchy scaly skin on my scalp has gone away. IMO, it's worth a try
Charm