I have a 5.7 and can send pix.
You don't need bridle or "4-way" adjustable system, it's overkill for an old cruising cat like this.
The std location for jib block mounting is on a pair of short tracks. These tracks are located where trampoline meets the hull, near the side shrouds. If they're not mounted on the boat, and you're going to add them, you'll want to work out a way to have good backing for the screws/rivets (porthole into hull?)
Some boats don't have the tracks, that's OK to just mount them to a single point. However you mount you jib blocks, you'll find that you need a small "pigtail" to keep the cleat part of the jib blocks, up off the deck. Otherwise, when under load, and you try to uncleat, it will be difficult to get it to release from the cleat. If it's up off the deck, you'll be able to just flick it and unsheet.
jim casto
NACRA 5.7 "Wind over Water"
Lake Travis, TX