'85 C10 Distributor

I have an '85 C10 and am wondering if it is possible the previous owner installed a 6 cylinder distributor in it. I think that the engine is a 305 but have not cleaned the engine off to get at the numbers yet. I know that someting is fishy just haven't figured out what yet. Thanks Paul.

Thanks for you that viewed, I figured it out with the help of my local NAPA it is a 4.3L distributor now I just have to change it.