You could try making the parts of the body and the shirt that are poking through the jacket, invisible using the paramenter dials or hierarchy editor.

You could use magnets to "pull out" the clothing from inside the body parts.

You could use something like "The Tailor" availabale at Daz, to transfer some of M3's body morphs to the clothing so that you can morph up the clothing.

You could use Wardrobe Wizard by PhilC and Kamilche to convert the base clothing to fit the morphed up figure.

So far as the shirt poking through the jacket, I've found that the quick fix to that is to make that part of the shirt invisible, and if it's in an area where that is not possible, I usually just use the clone brush in post work and clone over some of the jacket material.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi