Where can I find the motor number on my stock 1993 Suburban?

Am titling my Suburban in NC (moving from out of state) and need a power of attorney to
complete the process (http://www.ncdot.gov/download/dmv/VR_MVR63.pdf).  The POA
form asks for my serial number (assume that's the VIN) and my "motor number". Have
never been asked for the latter.   Have looked in all my paperwork --back to the original
window information sheet--and cannot find anything identified as a "motor number".  On
the original window sheet with the vehicle description there is a set of five characters  at
the bottom of the gas mileage section (lower left).  From left to right the numbers are the
easily-identified VIN, the number 16566, the character set 1GG1115174; the character set
Z2029033;  and the letters CKJ.  Am guessing that one of the two character sets may be a
motor number.  Any clues?   Called a local Chevy dealer and "stumped the panel".  
Thanks for any help you can provide.