Sort on one column not in group

I would like to know if this can be done. The groups in the report so far are Order and Part#

Some parts are coded as Inventoried. In another table the part# will have 'INV' in field IARRC6.

They want the ones which are INV to show first. THey want a col 'Y" if its INV which i have done.

Currently the output is this:

Order 123

Part#   Qty     INV

Eng       1

Nail        2     Y

Hammer  3

Rock       4     Y

so how to show Nail and Rock as first, also they should be in alphabetical order which should be ok as the list currently goes by alpha order on that one.