[Woodz428]

They went to 6 bolt in either '64 1/2 or '65, so if it is a '66 Bellhousing you should be fine. I'm not up on the changes ine Blowproof housings, but if it was made in '66 wou might want to see what improvements have been made since. It would be a shame to buy it and have the expectation that it will protect your lower extremeties and then have it not be as strong as it could be