Hey there Gary,
Does your boat already have a sloop bridle? Most boats do, but there are a few cat rig boats out there that have a twin forestay, or a high bridle setup, to reduce the load on the hulls.
This (
http://s51.photobucket.com/user/vmca/media/MosquitoRigging/riggin_2006_0917AM.jpg.html) is a cat rig high bridle, if yours is like this, you would need to change the fore-stay setup so that the two bridle wires join at a lower point to accommodate the jib. Check the Mozzie Building rules in the documents folder of (
www.theracingcat.com), as the lower the bridle, the more pulling force on the hulls, so there is a minimum height included in the rules.
The jib is usually zipped to the fore-stay, so you would need to add a block somewhere near the top of the fore-stay for the jib halyard.
The jib blocks on most of the boats are shackled to some loops of dyneema on the tramp. This way the jib setup can easily be removed when sailing solo, and the jib angle can be adjusted by shackling to different loops.
http://s51.photobucket.com/user/vmca/media/MosquitoRigging/riggin_2006_0917BO.jpg.htmlCheck out the pictures in the photo album below to give you some further guidance.
http://s51.photobucket.com/albums/f392/vmca/ Good luck!