I haven't used a davit but I did tow my Capri behind a Catalina 36 for 5 days. I raised the rudder all the way up. And raised the centerboard nearly all the way up, just enough for a couple of inches of the centerboard to be trailing. This allows the boat to track straight. It took a little playing around to get a good length of line for towing.
I'm trying to use a davit so I can store the boat on a trailer in my backyard and just lift it up and drop it right in the harbor when I'm ready to go. Any suggestions for mounting points on the boat? Think the shroud plates would be strong enough? Or maybe the hiking strap connection at the stern? Otherwise I might have to make up two straps that go under the boat.
No doubt you'll get more informed replies, but until then I'd really be leery using anything you've mentioned to support the entire boat's weight. I think a double looped harness would be safer. Check with a hoist/crane operator who does these transfers all day.
At Mission Bay YC , Capri 14.2s are all hoisted into (and out of) the water off of their trailers by use of an electric hoist(crane). We use rope line bridles that connect to the shroud bases with snap hooks and shackles and to the hiking strap bracket on the transom. A few have a loop of line tied thru the transom drain holes and clip to that loop instead of the hiking bracket. Works great , boats weigh less than 400lbs all up so you're not lifting much.
I do as Fan suggested. I have place two loop style shackles on the shrouds, and then loop a lifting bridle down thru the drain holes in the transom. I then lift the boat from the trailer utilizing a lift at our sailing club. I works great. I will try to get out to the club this week and take some pictures for you.
finally got out to the boat to take some pictures of how I rigged to to be lifted. You lift by the stainless ring in the center. You can adjust the lines going back to the transom to adjust your balance point. Once I have them adjusted, then I left one of them always attached, the lines attached to the shrouds unclip and I untie one of the lines running to the transom.
I hang a 14.5ft, 360# sailboat off a pair of 500# capacity davits from my dock. One davit grabs bow from bow eye and the other has a y that grabs stern from both sides thru a pair of bow eyes bolted to stern on each side of stern about 18" from centerboard. It is pretty stable .
You can make the stern y at west marine rigging using sailboat and anchor gear.