Metal restoration surface finish

Hey guys, Simple question I hope. I am in the process of tearing down my 68 NB and I am wondering about cleaning up the rusty bits like the jack, interior parts (e.g. ash tray), suspension and so forth.

My question is once I blast the stuff clean, what sort of surface prep is needed to keep the bare metal parts from rusting AND to make them look like original? I was looking at the ash tray and it has a particular finish that if I blast might not look the same.

Just wondering what the restoration guys are doing.

Thanks in advance.