I need to get a set of spring perches.. One set is $13 (.625 hole and 2.500" wide) and the other is $43 (.520 hole and 2.8125" wide)

Why are there two different styles? And which style is for what application? And why the big price difference? I am using SS springs for this application if that helps. I don't have anything to look at right now other wise I would measure it myself for you guys that were wondering


SDG Motorsports
Hellcat Demon and Redeye Supercharger CNC Porting
https://www.sdgmotorsports.com/