Using Excel 2003, I'm having trouble with dependent lists in data validation.
Here is the example:

There are 3 vehicle types (Prime Movers, Rigids and Other Equipment). On
selecting one of these, the next column shows up only those vehicle
configurations applying for each vehicle type. I've achieved this by use of
the INDIRECT function in the data valdiation set up. So far so good. (Level 1
dependent lists are working fine). The problem I have is when there is a
third list of data also dependent on the truck type eg the brand of the
vehicle type. There are different manufacturers for tankers compared with say
prime movers. I only want to see a list of the brands that apply for the
vehicle types selected in the first column of data.

I have already studied Contextures Data Validation Cheat Sheet which is
where I learnt to do the Level 1 dependent lists but not sure how to take it
to Level 2 and so on.

Any help most appreciated.