Re: 8" posi third member install
Most parts stores will rent you a puller for free once returned for the deposit. I'd pick one up before you start, the rear axles can be a bear to get loose some time. It looks like a slide hammer for pulling dents, a couple quick whacks and mine came sliding out. Reinstall took a few taps with a block of wood between the studs and a large rubber mallet and they snap back in.
Be sure to put a bottle of ford tracloc friction additive with the new oil.
Depending on what your planned use is, you may want to have the gears upgraded from 3.00 to 3.50:1, etc. at this time before install.
"If it isn't broke, I haven't fixed it yet" - Jon
'67 Coupe 289>333 AFR 165's, AOD, 9" 3.50:1, PDB
'09 Warriors in Pink w/glass roof - the wife's Mustang