This may not work with the preset scaling from the Poser Figure menu but should work if you manually scale the base figure.

1. Manually scale the base figure.
2. Conform the clothing to the figure.
3. Poser menu Window > Python Scripts
4. Click the top button in the Python Scripts window labeled "Wardrobe Wizard"
5. Click Utilities > Figure > More
6. Ensure that the base figure is selected in the scene.
7. Click the Python Script button "Copy Scaling"
8. Select the clothing figure in the scene.
9. Click the Python Script button "Paste Scaling"

See if that works for you.