Help ID'ing a Lower Unit

[csvencer]

Can anyone help me ID this LU? I am thinking it is a 90's 20" V6 OMC but the different length shift and drive shafts are throwing me off. Top of the waterpump to the drive shaft tip is ~18". Any help would be great. Thanks.

-Svence

https://lh3.googleusercontent.com/-UvkWbapP4Ys/T_Gn3F7tLoI/AAAAAAAAJig/0HJ761nIjEg/s800/P6120361.JPG

https://lh4.googleusercontent.com/-xR2kr1VW5Ns/T_Gn31VPYnI/AAAAAAAAJX8/moiKkkS7hvk/s800/P6120362.JPG

[cterrebonne]

the prop shaft size should give it away. kind of looks like a v-4 LU