To quote the 110 expert, John Vasco...
"The C-7 variant was essentially a 'C' airframe fitted with a central bomb rack. Many damaged 'C' airframes were repaired and retro-fitted with bomb racks."
Unfortunately the true fighter-bomber version of the 110, the D-0/B did not materialize in the sim for whatever reasons. This is the version Erp.210 used throughout the battle(for the most part) and the D series was just as important(numerically) as the C series during mid/late 1940.
Truthfully I wish 1C would have provided us with the following series:C-1, C-4, D-0/B, and D-3. On the fun list I would prefer the C-6(30mm kanones are fun!) and the D-0(pregnant 110!) for the obvious reasons.
Can't have too many 110s if ya ask me!