Article says he started saving an average of 2.5 cents per day in 1977. It also says that he saved over 62,000 cents. There are 12,784 days in 35yr. That would suggest an average of 4.85 cents per day. For the sake of this academic exercise, we'll split it and say 3.675 is the average number of cents he saved per day.
Obviously, from 1977 to 1982 all of what he saved were 95% (3.675 x 365 x 5 = 6,707).
Assuming a linear decline in percentage of 95% cents from 100% in 1982 to 28% in 2012, copper % can be assumed to be 64% as an average over the entire period. Thus (3.675 x 365 x 30) x 0.64 = 25,754 95% and (3.675 x 365 x 30) x 0.36 = 14,487 Zn'ers.
Assuming an average of 0.5% wheats for the 32,461 95% cents, there were 163 wheat back cents.
In summary, 32,298 95% Cu Memorial cents, 14,487 Zn Memorial cents, and 163 95% Cu Wheat cents.
Mind you the article says $620 face value. Our analysis accounts for $470 face value. Any way around, it sounds like a few afternoons with the sorter.