Scuncio Chevelle ex-L78

[TomN]

Having the bumper back on and everything together....today I pulled the axles and differential out of the rear-end.
Before removing things I tried rotating the driver side wheel forward to see if the passenger side wheel also turned forward. It sort of did, but not like the posi was really working well.
With the rear cover off I could see that it did have a posi diff., so I'm thinking probably a 4:10 gear. Counting gear teeth I had a 3:08.
Funny thing to me was the carrier had 1 thick shim on one side and 1 thick shim on the other side. Like it was a factory install.....I think.
i will have to have a close look now at the posi diff. to see what it needs.
I have a complete 3:31 posi rear out of a 70 Chevelle but don't think the gear change would make a 'big' enough difference on acceleration to give up the highway drivability of the 3:08's.
Thoughts ?