1) I created an SSDT_USB.aml for "8086_1d26" (HP11,12,13,14,15,16,17,18) and "8086_1d2d" (HP21,22) per instructions, and the IOReg always displays the full HPxx range (11-18 & 21-28) 16 ports. I couldn't get it to only show the 10 ports in the SSDT.
2) Next I took RehabMan’s SSDT-UIAC-ALL.dsl...