Slitherine

I understand that you base a skirmisher attachment on a 40x30 mm base that substitutes one of the unit's base.
Same thing for an artillery attachment.
But, how do you model a cavalry attachment on an infantry unit or an officer attachment?
Do I have to substitute a base with another 40x30 base or just add a mounted figure adjacent to the unit as a marker?
In the first case how should I model the base so that a cavalry attachment looks different than the officer attachment?
In the second case how should I differentiate the cavalry attachment marker from the officer attachment marker, and these from the AdC (used for CPs) on the table?

For a cavalry attachment just substitute any cavalry base for one of the infantry bases. Cavalry attachments replace a rear rank base.
BC attachment replaces a front rank infantry base with a heroic looking general plus some sundry figures to make the base look good (i use a mounted colonel and an adc)

In both cases the attachment base is a standard 40x30

We do it slightly different but are using 28 mm figs. Artillery attachments are a single gun, 25mm no crews on a separate shallow base, same frontage as other bases. Brigadiers are a single figure on a 20mm wide base, just deep enough for the horse figure. He can be placed beside or out front of his unit wherever he can fit. ADC's single figure on 20mm wide by same depth as infantry base, so the look like extension of command base. Longer base makes it easier to differentiate from brigadiers.
Cavalry attachments I just use a spare unit base.

Just an alternate thought.