i dont see how you almost died from no shifter boot..... i ran my truck for over a year with no shifter boot... and i had an open exhuast, it ended after the cat.... so basically a foot away from the hole in the floor.....
the lce is fine, it exits in the stock location, it should not interfere with the mc bumper, as the mc bumper is designed to be tucked up higher than the stock bumper, and the stock exhuast doesnt hit the stock bumper