Why is water antifreeze coming out between block and transmission on 1973 350?

There is 2 freeze plugs between the rear of the engine and the transmission. The freeze plugs are in the back of the engine block. Do not bother the big plug that is in the center of the block, That is the cam plug NOT A FREEZE PLUG.

YOu will either have to pull the transmission are the engine to replace those 2 plugs.