Flex-aLite fan for Slant 6?

I have been looking around can't really seem to find a flex-a-lite fan for a slant 6. I saw one guy say that you should order a fan that is one inch shorter in diameter than your factory fan to allow for flexing I guess?

I just know that Champion radiator really broke it off in me because this 3 row radiator is a straight up space hog and even when I completely remove the fan spacer I am going to be cutting it close with my factory fan if I can even use it at all...

I don't want to go with an electric SPAL fan because there are no ready made kits to install one. In fact, the details are very sparse on how to install a SPAL pusher fan to a champion radiator. I'd rather not have to mess with a radiator probe and fabricate some way to get the fan on there.

I am need of a really effective low profile mechanical fan to replace my factory fan.

Has anyone one else been in this position and successfully found a good after market fan.

The car has a 225 slant 6, 1 barrel carb. no power steering or air conditioning