Changing a Battery in mac pro 3.1

Roy, see if this helps:"

Tools

No tools are required for this procedure. You may, however, find a flat-blade screwdriver useful in removing the battery from its holder.

Preliminary Steps

Before you begin, open the computer, lay it on its side with the access side facing up, and remove any PCI Express cards that block access to the battery.

Part Location

Procedure

1.Slide the battery out from underneath the battery holder’s metal clip.

2.Remove the battery from its holder.

Replacement Note: Insert the new battery into the holder, making sure the battery’s positive symbol (+) faces up.

Warning: Installing the battery incorrectly may cause an explosion. Be sure the battery’s positive and negative sides are correctly oriented in the holder. Use only the same type of battery or an equivalent recommended by the manufacturer of the original.

Important: Batteries contain chemicals, some of which may be harmful to the environment. Please dispose of used batteries according to your local environmental laws and guidelines.....:-)

Hope this helps, good luck