well i just listed everthing you will need and the computer just crashed : (
here we go again if your caddy was a little newer it would have the gm data II bus connector that would have somthing to do with the door chime and airbags the adapter for that is a little pricey like 150 bux.
you should need the following parts for the install
metra # 99-4500 Dash Kit
# 40-gm10 Ant adapter
# and if it has the bose system you will need the soungate part ????? **** I forgot the # or just a metra 70-1858 if it doesnt