on my 54 the striker is adjustable and the manual gives some instruction to adjust it. although i thought it needed tweeking even after that.
(from memory)i think its three clutch head screws. loosen them, slide the striker out as much as the slotted holes will allow, close the door, open the door and tighten the bolts. this didnt seem to take into account the compression of the weather strip so i just slid the striker in another fraction of an inch.
