Looking to build a shortblock.
 

I have a '91 150 longbed that I want to build an engine for, my question is what block and heads should I start with? Was there a certain plant in a certain year that built the best? Are there part numbers I should be looking for? She isn't gonna be a bruiser but since this will be my first solo project I want to do it right. 'This truck is never going to be sold' kinda thing. Any help is greatly appreciated.