I've got a 69 cutlass S installing under dash courtesy light harness. The new harness came with out bulbs what size or # bulbs are suppose to be in it ???
Thanks Craig

 

Your Chassis Service Manual (page 12-63) says 90 for "courtesy light."

If I recall, the 90s are the same ones used in the rear armrest lights of the convertibles, with two pins on the bottom that connect to the filament, and no connection to the base.
Check the configuration of the sockets to be sure this is accurate.

- Eric

 

90 is the correct bulb to use.

 

I threw in 1004's (modern number) and they worked perfect.

 

Thanks on the replies got 90 or 1004 update #.