Factory cross-member mod ???

[Spray-Bomb]

I plan to run 3" exhaust on my truck & was wondering how big of holes I can cut in my cross-member that holds the carrier, without making it weak

I was thinking a 4" hole for each pipe would be enough clearance, but would this weaken it so much that I would need to weld in some additional "support metal" to make it strong again?

Please, no comments like ( 3" is too big )

Also has anyone ran the CherryBomb Extreme mufflers ?

Thanks, Matt