Did the parent originally talk about dysgraphia? Because while I have pretty serious dysgraphia I'm not really dyslexic. While related they're pretty significantly different. One of my best friends growing up had dyslexia and with my dysgraphia we always joked about being one 'normal' person.
No. At age 60, when I was 12 they really didn't have a name for any of this. For years my school records had be as retarded. It was not until I taught myself calculus and trig in the 8th grade that my parent new something was wrong and sent teaching specialists at OU. They a used the word dyslexia. This was all very new in the 60s.
I was experimenting with character substitution too, but it won't work well with a variable width font, since the words at the end of the page moves a lot.