Wow! Schnool, that is a spectacular example of a 1970's radial head spinnaker! I have one alot like it that came with my boat, although it is not quite as ....colourful!
You will need pretty long sheets to run your asymetric properly, but once you buy them you will be able to use them for the symetric chute as well. Double the length of the boat is a good rule of thumb.
You should shackle a couple of blocks quite far aft on your toe rails to fly the sheets from, and then deflect forward to another block that will give you a good angle to a winch. you might want to consider using ratchet blocks in the system to allow you to have better control in conditions where winches aren't required. As for the downhaul, if the boat has been rigged for spins in the past there must be a padeye on the foredeck to put a block on, if not you could consider running it from the base of the mast,while such a setup has it's advantages, it is less forgiving than a downhaul directly under the pole.
If you take pics of your deck layout we could probably get more specific, and I would be curious to see pics of your sails too!