Hello to all. I am curious if any of you have swapped in a newer model posi diff into a 66/67 GTO. When I mean newer i mean 68 to 72. The reason I ask is I want to replace my 3:55 non posi diff with a posi diff with higher gears. I know that Eaton, auburn etc has a posi center section available. I have access to some late 1960's era GM cars. I have not gone out to measure any diff widths yet. I was just wondering if anyone has done this and what they used for the replacement differentail. Thank You!