Hello,
I had made the mistake of constraining and parenting both foot and left arm manipulators to my geometry without freezing the transformations and got pretty far in my rigging afterwards.
I tried unparenting first (which didn’t work) and then I tried to unparent THEN perform a Constrain–>Remove Target command, but got this error:
Contents/scripts/others/doRemoveConstraintTarget.mel line 133: A constrained object must be the last object selected.
I might just be performing these commands incorrectly, but I’d love to hear feedback and suggestions on how I can do this without going through the rigging process all over again 
Please let me know if I’ve described this clearly enough. Sorry if this question seems inane. I’m pretty new to Maya and still making classic newbie mistakes.
Much Thanks!