The Rovering Member, jp928, GRTV8 and SydneyRoverP6B have said it all already!
I wouldn't use the two fittings at either corner of the boot floor, they'll just separate at the weld. Ask me how I know!
At the front, if it is a 3500, don't use the guard for the oil filter! Use the main front crossmember, further back than the bolt-on panel beneath the radiator. Or the bumper irons.