B737 manual gear ext.
 

After a local incident recently where a 737 NLG had to be extended manually I was wondering what the manual procedure/method was for this a/c.

Is it a cable pull releasing the uplock then gravity doing the rest? Likewise the mains?

Yes. Handle is located on floor behind the First Officer's seat. Lift door and pull handle. Free fall. The next generation (-700 etc.)has a micro switch built in to the door when opened it deactivates the gear handle. We have had a few aircraft that could not raise the gear because that door was not completely shut.