I just viewed the picture of your truck posted in the welcome forum. From the picture, that appears to be an outstanding, beautiful original looking truck. Someone has obviously put a lot of effort and money into keeping it original right down to the pinstripes. Trucks in this condition are pretty rare; - I’ve only seen a couple in this region. If this is the case, do not discard the original 216 engine. Put it in storage as this will make the truck more valuable if you ever resale. If you just want to enjoy driving the truck without worries, the 235 is the obvious option. If you want to retain the trucks value as an antique, keep the 216 on hand, rebuilt or not. You can have the best of both worlds.