If you have one can you e-mail me. I have a couple of questions.

ADTECH,

    Post your question here...I am sure there are others on this board that would be interested.  This website is an outstanding resource...and it makes it easier for others to do a quick search for quick answers to questions.  Do a search under "ZM" or "Z-M" and you may find the answers your looking for.  If you don't feel comfortable posting your question, just drop me an email.

RLTW

Well what I am trying to find out is if the Reciever section can be replaced easily (I figure I would need to drill and ream the gas tube hole) with another standerd AR Upper reciever, like the DPMS Southpaw.

The recivers are probally not interchangable.  The forward assist on the ZM is set forward to acomidate the shorter bolt carrier.  Also the bolt carrier itself is righthanded (you could probally make one of these by cutting short a standard left hand carrier).  You might try calling Allan at ZM and see if he has ever done any left hand setups.