  In March 2006, the Hubble Heritage Team obtained a large four-filter (B, V,
I, and H-alpha) six-point mosaic dataset of the prototypical starburst galaxy
NGC 3034 (M82), with the Advanced Camera for Surveys (ACS) onboard the Hubble
Space Telescope (HST). The resulting color composite Heritage image was
released in April 2006, to celebrate Hubble's 16th anniversary. Cycle 15 HST
proposers were encouraged to submit General Observer and Archival Research
proposals to complement or analyze this unique dataset. Since our M82 mosaics
represent a significant investment of expert processing beyond the standard
archival products, we will also release our drizzle combined FITS data as a
High Level Science Product via the Multimission Archive at STScI (MAST) on
December 31, 2006. This paper documents the key aspects of the observing
program and image processing: calibration, image registration and combination
(drizzling), and the rejection of cosmic rays and detector artifacts. Our
processed FITS mosaics and related information can be downloaded from
http://archive.stsci.edu/prepds/m82/
