I reckon unless it is a 308 example and a concours resto it won't matter too much, especially if it is a less than desirable colour (like Durham Beige). Just do what you please. My only advice would be to use a period colour correct for the month/year if you don't go original. If the Sandman is a very desirable colour though like Orchid, Absinth or Valencia etc you'd be mad to change it. Personally if I found say an L31 HJ Kingswood Sandman ute in Mint Julip that needed paint i'd respray it something nice rather than put up with it. If it was a colour I could put up with but didn't really want like say Jade Green or Mandarin Red or Persian Sand i'd make it that colour and live with it.