Leaf spring perches for a ford 9

[67rstbkt]

On the ford 9 I have for my firebird, it looks to me like the axle tubes are larger compared to the 10 bolt. Will the stock GM replacement perches fit? Is there a different set or size I should be looking at? Thanks

*Edit* I measured and they are slightly larger at 3.25 while the GM perch is made for a 3"
So what are you guys using? Is there a 3.25 version that I'm missing or should I be picking up one of those universal ones in that size? I'll be using this for the lower links on my Ridetech setup.