I did it on mine,plus used some Flex Seal in addition.
It added quite a bit of weight but it sure makes the body a LOT stronger.
In your case,I would use some masking tape on the outside of the body first and try to get the broken body parts
back to as close as possible to their original position.
This will also help prevent the Shoo Goo from oozing out of the cracks and getting smeared on the outside.
Procedure....it's pretty easy to do.
First really clean the inside of the body with some Dawn soap and a Scotch Brite pad.....the cleaner it is the
better the Shoo Goo will stick.
Let the body dry completely.
Then tape the body on the outside where the cracks/holes are.
Wear some rubber gloves and smear a liberal amount of Shoo Goo on the inside of the body.
As you do 1 section of the body,lay a piece of the drywall mesh tape (NOT THE PAPER TYPE) on top of the SG.
Where the big holes are I would use a double layer of the dry wall mesh.
Force the tape down into all the nooks and crannies of the body with your fingers or use a plastic knife to get the tight spots.
After you get the whole body done this way,fill in any dry spots with more SG,you might need 2 tubes of Shoo Goo.
In a couple hours the Shoo Goo should cure pretty well.
If you decide to finish off the job with some Flex Seal,DO IT IN A WELL VENTILATED AREA!
That crap smells really bad!
Here's what it'll look like: