Maybe not rare, but too nicely original to heavily modify.
Your car, your money. But I'd keep and modify the slant as you see fit. But nothing that couldn't be put back to original. New seat cover to bring the interior back to stock appearing and new vinyl top. New wheels and tires and polish the factory paint.
Original factory appearance with 'day 2' modifications, then "WOW" the show spectators when you pop the hood and show a modified slant!
JMO that you didn't ask for.
