Puller electric fan with 4 core radiator?

Exactly right. By the time you get to the 3rd & 4th row of tubes, they add little to the cooling ability of the radiator.
Best solution is clutch fan. There is a myth that elec fans do not cost power. They do cost some power & the amount will vary with the fan motor rating. A higher rated alt is also likely to be reqd.
I have a three row in Vixen and the ONLY REASON I have it is because I snagged it NEW on a scratch and dent sale on Ebay for 89 bucks SHIPPED. Other than that, I'd have a two row. BUT, I really believe I could remove the fan and throw it in the ditch and it still would not over heat. It's just a little four blade fan anyway. But I tell you what. That radiator is a coolin MUG. 171 degrees in and 79 degrees out. It's FLAT doin it.