Read the many reviews and decided it was time to order as I was tired of exhaust noise on start up. I was able to install this from the bottom of truck. I drove truck up on ramps and worked from the bottom. Did not see that removing fender well on that side would be easy. My truck had a ground bonding strap bolted into head where the top bolt of bracket goes. Removed it with ratcheting wrench and then installed the bottom bolt to hold bracket in place. Then I put bonding strap on bolt and worked bolt into the hole in the head. Not much room and took about 5 minutes but it worked. Used a racheting wrench and regular closed end wrench to tighten it. No way to get torque wrench in that space so just went as far as I could go with wrench. Used the red locktite on all bolts as per instructions. Started truck and no more exhaust noise!! These work really well and I finished job in half hour by installing from underneath truck. Saved lots of time.