Yup. The later North American Mk3's, of course, came with "normal" seat belts, thank God.I believe you need new doors, seat belts and B Pillar trim, etc. More work than it is worth if you ask me.
What about the pyrotechnic pre-tensioners that are located inside the front door sills with manual belts? I wouldn't think the auto belts had those... but maybe, for the lap belt...Pretty simple really