Thank you. Can you clarify the statement below about applying the fixed obj to the original clothing? I'm not sure I understand what you mean.

This also sounds like I better want to convert something really bad for this much work with the morphs, for where autofit just won't do.

 

Apply the fixed obj to the original clothing and turn on the morph. Apply each morph you want to use, then export that as an obj. This will give you the clothing morphs in relation to your fixed obj.

Then take those objs and use morph loader pro and load those morphs in the new clothing. You can then set proprerties for putting the morphs in new groups, limits, colors, etc... 

Save those morphs by using File -> Save As -> Suppport Asset -> Morph Asset (s)

Give it a product name (call it whatever you want), then check off the imported morphs and click OK.

Now you should have the morphs in your clothing.