Rest assured your trim code 642 Suburban is a Blue Plaid Highlander.
Being a Highlander Trim upgrade it will have the Highlander goodies like the plaid and black carpet but none of the Promo Package options were included.
All other options on your Suburban (other than the Z62 Custom Deluxe) were free choice. This is why your Sub was built with the base mirrors and not the DG4s "included" with Promo Package A or higher as an example.
Reference old thread
http://67-72chevytrucks.com/vboard/s...9&postcount=52