Not only did they have Zimm, they should not be seen without it. As for side skirts, I am sure they could carry them, but photo's of early versions with them seem to be hard to find, most seem to be mid or late productions. You can see from this vehicle it has the welded on matlet and the stowage further forward, but has the 2 piece barrel.
Dragon kit 6494 gives you these options and is pre Zimmed. But, it doesn't seem to come with the skirts, these may have to be AM.
I am a Norfolk man and i glory in being so
On the bench: Airfix 1/72nd Harrier GR.3/Fujimi 1/72nd Ju 87D-3