any advantage to a 5.2 over a 5.9 ?

Around here price is about the same for both motors... 350-500 pending on mileage. Advantages of the 318 will be gas mileage, internally balanced, and if staying with he factory cam, the 318 magnums have a little hotter cam from the factory. If you can find a '92 318, it will have even more of a hotter cam, and around 5000 rpm's, may pull harder than a 360 mag.