im not sure about the waterpump direction with the serpintine belt, thats a late style sbc. the main reason i have not run any vortec heads is the amount of work that is needed to run them, i.e.: matching intake, weak springs. changing springs is easy but, if you are on a budget, the cost of the vortecs, manifold, valvesprings, can be more than haveing someone port out a set of older heads. Im probobly going to tick people off by saying that but from where I live stock vortecs run at about 400 canadian a pair. then the matching intake.......etc. good money that could be spent on porting a set of heads and swapping out the cam. Just my opinion. I have been porting my own heads for over 20 years, so its a cheap way for me to gain the flow. back to the serpintine system, i am really unsure of its direction to the flow but from the configuration of the water pump, i should spin in the same direction, unless gm changed something. I am not familiar with early 90's sbc. I have only used pre 85 small blocks. and the heads i have kickin around my house are the same 85 and earlier, hope this helps........