Setting up a Spinnaker

I'm taking a week off at the end of September to go sailing with two friends and we want to see how far we can go from Anglesey returning to Liverpool, maybe off to Dublin and IoM; probably will blow a gale but thought I would rig up the Spinnaker to provide a few more options ! I'm used to using spinnakers on dinghy's and used it once on my old boat but never had it set up the Contessa so hopefully you can help!

Top Halyard  - There is spare forward block at the top of the mast, which I can use for the top clew.....what length and width halyard do I need (will only go to base of mast, no lines are led back)

Uphaul - No problem there is a block already on the mast just below the streaming light and there is already a halyard

Downhaul - Will need a new halyard for this, there is a block attached about two feet behind the front forestay. I can probably guess the length but any suggestions helpful

Guys - Port And Starboard; I know these need to the back of the boat through blocks and then to the small spinnaker winches; but any suggestions on length and width again ?

Lastly spinnaker - this came with the boat and I laid it out in the garden - it's massive !

If I get this all workingand get it flying then I'll take some more pictures and post a tech note.

Thanks in advance for any help.

Cheers