Thanks to all

>INDEX ON Fld1 + str(-val(Fld2), 8, 2) + Fld3

should work fine. For some reason I thought it wouldn't, but I just tested it again after reading this and it works great

> chrtran( upper(lcStr), "ABCDEFGHIJKLMNOPQRSTUVWXYZ", "ZYXWVUTSRQPONMLKJIHGFEDCBA" )

This looks much faster than the algorithm I devised..

I'll test both. Thanks!

I also think I'll renew my long-lapsed UI membership...