Sho 250 Yam tilt trim Cap o ring ?

Have Yam 250 sho with main tilt cap leaking. Cap came loose and o ring is bad on cap. Question is, can I just pull the cap cylinder out a little and will the new O ring fit over the cap to fit into its groove, vs taking apart the cylinder to get 0 ring on?

If tilt ram you need to pull trim unit out and pull ram out and then replace orin. Any question PM me