Need help installing 40+ gallon aero tank

[Bgrdmoose]

Dropped the factory tank to install a 40+ gallon tank pulled from another '72 suburban. Trouble I'm having is the crossmember that sits in the trough is back to far and won't let the tank slide far enough forward & is causing the tank to hit the bottom of the rear crossmember near the bumper.

Can I grind down the rivets and move the crossmember forward 1/2in? I think that would allow the tank to slide forward enough.

I drove down to California and was hoping to get the tanks exchanged before I drive my suburban back to Seattle next week, I'm tired of stopping for gas every 2 hours.

[Bgrdmoose]

Ttt

[magicoolbus]

The easiest way to remove a factory rivet is to cut an x in the head with a cut off wheel and use a chisel to knock the head off. Takes only a minute. When you reinstall the cross member just use bolts.