Yes - 2 in each side. they are unusual in that they are 21w offset pin. They are very tricky to access until you understand how, in that you are reaching through an access panel then rear of the light and then each is set deep in the housing into long extension tubes.
The bulbs protrude into glass domes inside the clear or amber light unit.
Personally having stripped down and rebuilt more Z4 lights than decent dinners I'd suggest forget it by the time you have to add 21w resistors to avoid bulb errors and disrupted flash cycles, but am happy to be proved wrong