From the provided pictures it appears to be a Cheyenne as other posters have confirmed. But of course a SPID will tell us a lot. The build sheet would be a great cross check but it probably is not there. Please be sure to check the VIN plate rivets for alteration. Last thing I see is that the truck has the D99 molding that will only be found on factory Two-Tone trucks. The current color could be correct but it was apparently a Two-Tone and that would be on the SPID.
Here are links to a '72 chart and paint codes.
http://www.tcpglobal.com/aclchip.asp...truck-pg01.jpg
http://www.tcpglobal.com/aclchip.asp...truck-pg02.jpg