How to remove door check strap bumper from passenger side?

[IIA]

I'd like to replace the rubber bumper on the end of the door check strap rods. I've got the kind with the metal tube on the underside of the dash. The one on the driver's side (LHD) comes out easily when I disconnect the pin connecting the rod to the door - it just slides out from the inside end of the tube. But on the passenger side, that side of the tube is blocked by the heater ductwork. Even if I could slide it out a little and cut the existing bumper in half to remove it, I wouldn't be able to get the new one in. The tube appears to be welded together so I can't disassemble. Has anyone done this?

[tluchette69]

I thought I responded to this but maybe it was another forum. You just need to remove a couple of the screws holding the heater distribution box to the bulkhead closest to the passenger door and it will drop down far enough to slide the old one out and install the new.