Havent got a 93 FSM ... but the '93 part number is J323 9375.

From the '94 and onwards FSM's

RADIATOR PRESSURE CAP
All radiators are equipped with a pressure cap.
This cap releases pressure at some point within a range of 83-110 kPa (12-16 psi). The pressure relief point (in pounds) is engraved on top of the cap (Fig. 5).


Fig. 5 in those FSMs ... show a cap with 16psi marked on it.