Isometric dimensioning - AutoCAD

I received the following email from a fellow piper and wondered if any of you can help out.

We are about to draw some isometric piping soon on Autocad (not by hand)
I am looking for a simple isometric dimensioning that is automatic that possibly uses lisp routines that sits on Autocad.
I had seen one years ago from the internet, but had lost the connection, I have no idea where it is and I have spent a lot of time looking.
Can you help