interior colors are definitely a hard one
personally i like a uniform look, maby keep all the seats black, gray and black door panels and a gray headliner and carpet?
its really personal preference. I know your not going for a stock look but one thing to consider is if you plan on driving your car often is wolfsberg west makes a kind of OE style carpet and rubber mat set up that cleans really easy and i think looks good to, ive got wolfsberg carpet and rubber mats in my '60, i love them! they don't glue down or anything so its pretty cheep and easy to replace if they get messed up
its kind of hard to see but basically its carpet around the edges and a molded rubber mat that goes over the tunnel and pan sections