Hey man, do yourself a big favor and do a search on here for flex fans and read the horror stories. I agree with Longhornman, the heck with a flex fan. A good clutch fan and you should be fine. And Cdowns is right on also, I blew a headgasket in my '88 s-10 because I was going by the almost 20 year old "factory" gauge that read I was just fine, til the truck started missing, then it was too late. Just shows ya you can't trust those gauges all the time. Now would be a cool time to have an excuse to get new auto meter gauges for the dash.
..............................Bamm