So I found a technical manual document with the conversion tables for enterprise and unified scoring. I've used the Enterprise scoring for these:

Reading = GE 10.3, 90th %ile, NCE 77.0
Math = GE 12.0, 92nd %ile (first month of grade 6), NCE 79.6

https://www.renaissance.com/act-sat-benchmark-tool/

There's some other stuff on this page too, for predicting ACT/SAT on-track progress, but also three little links to the technical manuals, which is where I found the conversion tables.

HTH
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