Hi Bpaolini!
You're automatically a member of the "Happy
Caravel Owner's Club"

just by virtue of having a '67
Caravel. Congrats! See our posts under the 1965-1968 Caravel forum.
My 68 Caravel has a replaced fresh water tank. The new tank does not have a gauge for water level, which is a real nuisance when boondocking. I plan to add one. For now, I and another Caravel owner have to remove the cushions, put a flashlight on the side of the tank, and rock the trailer to see how much water we have left. So I'd seriously look into a nice gauge when you put in the new tank.
Just downstream of the tank my new plumbing has (in this order):
(1) a valve to divert the tank water to the dump, which exits the trailer through a hole in the floor;
(2) a blow-out plug in the water line. This allows me to connect an air compressor to blow out the lines.
(3) a shut-off valve for servicing, or emergencies (I've used this several times already when adjusting the water pump).
(4) a small water filter
(5) the water pump
(6) a small Shurflo accumulator (or pressure tank). This smooths out the flow and reduces pump cycling. I got it for about $37 via Camping World online.
It's all connected with plastic plumbing and there are quick-disconnects in the appropriate places.
Just FYI in case you are re-doing the plumbing at the same time.
-- RL