To 'put a figure morph into a clothing item' you don't use MorphManager, you use 'The Tailor' by codeTwister, it's in the daz store., It creates new morphs in clothing to match the morphs in the figure.

 

Plan B - Use Dforms to fit the clothes, then spawn them as morphs (not in ds 1301 - functionality broken, use ds 1201)