File:PT in CAS.jpg

Summary
Impregnate a Sim with PT's genetics, age the baby up and impregnate the baby with PT, age that baby up etc. until the other Sim's genetics die out and only PT's are left.

Then extract him/her from SimPE to BodyShop, and then enter CAS. Be sure to enable debug mode - What do you have? An almost, if not exact PT replica.