After the holes are drilled flip the chassis over and drill counter sinks in the bottom of the chassis using a 11/64” drill bit……  Now be careful here that you do not drill all the way through the chassis. Just do a little at a time and keep checking the depth.

Now mount the brackets to the chassis and mark the outside edge of the chassis. This is where you will start to make your first bend. Make the bend to about 90 degrees and then slip the body on. You may have to stretch the body over the brackets.

As you can see the brackets are too tall. Now start cutting them back a little at a time until the body start to sit right on the chassis.. Keep checking the fit so you don’t cut them too short.

Now comes the hard part J  Take a pair of needle nosed pliers and start carefully bending the brackets to fit the contour of the inside of the body. Keep checking the fit until you have it right. This can take some time depending on how much of a curve there is to the inside of the body.   

This is the important part of the mounting. When finished bending and fitting the brackets none of them must touch the insides of the body.

Okay let's prep the chassis now.  Steal some wax paper from your wife and cut if to size and then with some glue stick it to the top of the chassis. The wax paper will keep the epoxy from sticking to the chassis when it runs down..  And it will run down. But this will be normal so don’t freak out.

Now remount the brackets to the chassis. Be sure they go on in the same position they came off.

Now flip the chassis over and tape the excess wax paper to the bottom of the chassis to keep it out of the way and from interfering with the body.