Clutch Question

I"m looking for a new clutch for my pickup beings that i'm goign to be putting a lot more power to the ground. I found a kit on the internet but the size is slightly differen't from stock. The stock pressureplate is an 8.875" with a 1" spline and 23T The aftermarket one that i found is 8.5" 1" spline and 23T. If this will not work where would i start looking for something that i need?