Can someone explain to me or help me understand the diff ways to mount seats...i am looking at some sparco corsa and they say that they are only side mounting seats. I dont know what that mean? What are the pros and cons of each way?

 

most race bucket seats (fixed back) are "side mounts"
in other words, the bolt that holds the seat is located on the side of the seat, which require aftermarket seat brackets and sliders, which you would have to purchase seperately on top of the Corsas, usually about $150, makers like Sparco, Recaro, Buddy club, Nagisa, etc.
if you look at your evo seat, which pretty much falls in the category of aftermarket reclinable seats, (such as Sparco Torino) is bottom mount, the bolts are on the bottom. Usually it bolts right to the sliders. (I'm not sure if they bolt right to the stock sliders or not.
there are no real pro/cons, you just have to buy the bracket/sliders to accomodate the seat you want and to be able to install it in your car.

 

oh ok thanks..i see what your saying.