Help adding a unit

[The Colonel]

I dont want to necessarily add a unit to my Stainless Steel mod, but for my own personal use (not for release) I want to replace, say the model and texture for the Knights Hospitaller in stainless steel (the un-upgraded unit) for the BC one. How do I go about doing that?

[Eothese]

If the BC and SS versions differ, you will have to copy the mesh, texture and sprite files from one mod to the other. The battle_models.db will tell you which files to copy and to where, just search (ctrl+f) for the unit you want to change. Knights Hospitaller's will start with '19 knights_hospitaller'
There may be some differences between mods in 'ownership' of units, if this is the case you may have to repeat use some textures, or you could use merc if its available.
If you do want to add any units to the db, you will have to add to the serialization number by 1 for each unit and its armour upgrades. If your only replacing an existing model, you won't.