The 5.0 was factory equipped with diamond wires. The spreaders were adjustable. The factory recommended ~1.5-1.75 rear rake. I do not know what spreaders are on your boat but I would not sail with them.

I think the 5.0 used the 5.2 extrusion, which is pretty flexible. A good starting point for the 5.0 would be 1.75 aft rake with 200-300 lbs tension. This is something close to how they set the boat when it was new, beyond that it is up to you.

The NACRA Manuals are available for download:

http://nacrasailing.com/index.php?option=com_phocadownload&view=category&id=1:manuals&Itemid=91

Try the Vintage

Good Luck