Issues grouping criteria toghether

[u_r_dream_en]

I am having troubles with the grouping in my report. I have two
tables. The first table “Schedule” holds the information for each
unit scheduled and the second “Model” identifies a model group by main
system number that is linked to the Schedule table. Both linked
fields are labeled “Item”. The issue here is that the main system
numbers can be identified uniquely by model. The option system
numbers are shared. For example:
There is a main system number for every UNIT # listed, if there are
options then there will be another row with the same UNIT # but a
different # listed in the ITEM column. In my report I group by date
then by serial number, with sorting for each day. The issue is when I
want to add another grouping by Model. Because only the system
numbers are referenced, the options that share the same UNIT # are
separated in the report. Hope this make sense. I would like to
either group MODEL then DATE then UNIT # or i would like to group by
DATE then MODEL then UNIT #. Any thought on making this happen?
MODEL TABLE

MODEL ITEM
ModelA 111111
ModelA 222222
ModelB 333333



SCHEDULE TABLE

DATE UNIT # ITEM
06-01-10 10000001 111111
06-01-10 10000001 Option1
06-01-10 10000001 Option2
06-01-10 10000002 222222
06-01-10 10000003 333333
06-01-10 10000003 Option1
06-01-10 10000004 333333
06-01-10 10000004 Option2

Thanks. - Diane