sense of logic - carving/tooling (if those required) comes before dying and before attachment to other parts (interiors, etc)
why? if you mess up with the coloring, while for example exterior(outer) part is glued/sewn to interior/body/piece, then you waste time, materials etc
not exactly - depends on dyes, leather type - vegetable leather will always change it's structure when dyed, even if it is 1" thick