Originally Posted by Army

More specific information about which 4 cylinder and 6 cylinder engines you mean - years - models - makes(?) etc will help!

I've started to compile information for this kind of question here

http://www.peachparts.com/shopforum/general-information/311136-fsm-epc-data-%3D-chassis-model-transmission-drive-train-information.html

Perhaps something there will help?