Setting admin password in TS

I have seen some similar posts but nothing that addresses my specific issue

I want to set the local admin password randomly during my TS or at the end,  this value will be sent to a password safe for later use.

I have tried setting the built-in admin password CS variable in code but that variable seems to be taken over by the task sequence.  So I am now using my own ts variable and set the password as one of the last steps in the TS.

This appears to be being reset by the TS to something else though.

Question is where can I run this task in the TS so that it is what I want it set it to.