If your at even a "true" 10.1 i'd run 1 step colder, I do not like Autolites, they tend to glaze under hard excelleration & hard to read, 85 is a stock plug for 8.5.1, too hot for the compression you have, I ran the NGK V-Power 5670-6s in my 9.73 451, -7s on juice, They are very easy to read, If you see any black specks or shinyness on the porcelin there too hot, Thats if the timing & curve is right along with the proper octane, There is also such thing as silent detination, the 1st. to show it is the plugs, I've had the best of luck running the NGKs, Another thing to remember, Back in the day there were 3 champion plugs for the 440, J13YC for the standard 440, J12YC for the HP & J11YC for the 6-pack 440 & there was good gas back then, If it didn't matter the heat range there would be 1 heat range fits all.
Have you calculated the true compression on this 440, unless you milled the heads some & are running a steel shim gasket & pistons are FTs around .017"-.019" below deck your not even at 10.1 with standard 91cc heads, close but definitly not 10.5.1