I'm running twin electrics on my 69 and I like them, but first let me ask you why you want to do this? Are you trying to solve a cooling problem, or are you looking for "free" horsepower by getting rid of the engine driven fan?
FYI, I'm also running a big aluminum radiator and my engine has been somewhat "surgically enhanced" to up the power. For a more or less stock setup, I agree that the original setup is probably the best and the most trouble-free. If you convert to electric(s), you're also going to have to up your game alternator-wise because the stock 65 amp alternator won't be able to keep up.