Someone told me 2:29 7.5", it is in a 78 El Camino. Is this correct?

Thanks,
Rick

That is correct for a 78 model.

Do you know how many splines?

Do you think this will work?

http://cgi.ebay.com/ebaymotors/Gm-7-5-7-625-7-5-8-28-Spine-Factory-Locker-10-bolt_W0QQitemZ290083692228QQihZ019QQcategoryZ33731 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem#ebayphotohos ting

Rick