Just my 2 cents. We went through a similar dilema years ago when we dropped a 350 V-8 into my buddies wifes Vega. After pondering electric fans, "which were new back then", we played around with fan blades, different clutch fans etc. After still not finding the solution, we got an entire radiator assembly out of a S-10 pickup. We got the radiator to fit into the support. It was a lot larger than the stock Vega. Not much of an improvement in cooling though. We then carefully cut the S-10's radiator shroud to fit. Unbelievable difference in cooling. The shroud was 85% of the solution. He eventually went on to put a dual pusher electric fan assembly in front of the radiator. He wanted the extra cooling capacity for drag strip trips. You may want to search the bone yards for a shroud that you could make work. It won't cost much, and may save some headaches.

 

Another story,.. Last Sunday I started my Mustang up in the garage. (Hasn't been out this yr yet).
I let it idle just to warm it up and asked the wife to turn it off if it went above 180 temp wise.
I went and continued to cut the grass. I came back 10 mins later and the car's over-flow tank was boiling
over like mad! I quick shut the thing off. Asked the wife why the hell didn't you shut the car off??
Said she thought it was just fine,.. (She was watching the wrong gauge she said). Asked her if all the
water steaming away could have giving her a clue? Anyways,.. My Be-Cool 16" 2950cfm fan took a crap.
So,.. Might want to keep that stock fan.