A good website for filling in the missing US vehicles is
http://www.globalsecurity.org/military/systems/ .
I have included all the Stryker variants, the FMTVs and the M88.
As for the M88, I copied the M60A1 data, used the icon for the Pioneer Panzer (West German) and changed the class, crew and et al.
I am still working on the MCBS series of M1's and formations.
Good luck and MobHack is way too easy to use.