Sherbert mini minky punishment bear Adult Pajama

This is a custom punishment bear made with sherbert rainbow mini minky fabric.  It will have solid eyes, a vinyl perforated nose, and locking zipper mouth.  (433) It will have the usual 5 locking zipper heads running from the back of the head, down thru the crotch, and up to waist level in the front. (30) There will also be 2 separate horizontal zippers at chest level. (70).

Which measurements should I make this for?  Is this a size up from the 3 separate plush suits, to be a 4th layer, or is this for the original "starting" size?