Load you base figure, IE: Vicky.  Add the clothing you want to use. Analyze it.  Then add your morphs to Vicky and then convert the clothing to her.   It's the same as if you were converting something from Vicky over the SP3. Only instead of deleting VIcky and loading SP3 to "convert to", you are adding morphs to the existing figure IE: Vicky.

"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