First, here's an exploded view of the 760 showing the parts:
http://www.again.net/~steve/page7a.htm
Here's disassembly instructions from The NRA Firearms Assembly 3:
1. Push out the receiver pins and remove the trigger plate assembly by sliding it forward and down.
2. Remove the magazine, press the action bar lock and open the action about half way.
With the bottom of the rifle UP on the bench, insert a snug fitting punch or steel rod through the holes in the action tube.
Unscrew the tube by turning the tube with the punch counterclockwise until it can be removed.
3. Close the action and remove the barrel, bolt and bolt carrier from the receiver.
4. Holding the bolt carrier, pull the barrel forward until the bolt releases from the barrel extension.
5. Push the bolt carrier with the bolt, free of the action bar.
6. Tilt the front of the fore arm downward and slide the barrel out between the action bars.
Once disassembled, the wood forearm is held on the action bar assembly just like a Remington 870 shotgun.
There's a round nut (Part #29) inside the front of the forearm that must be unscrewed to allow the wood to be slid forward and off the action bars.
This requires a special spanner wrench, which can be made from a section of steel pipe, or a piece of 1/8" thick steel plate.
WARNING: DO NOT try to unscrew the nut with pliers or poorly fitting tools, the thin action bar tube can be damaged if you slip.
Buy or make a good tool for this.
To reassemble, reverse.
When reassembling the barrel into the fore end assembly, don't spread the action bars more than necessary to get the barrel bracket (Part #23) into place.
To reassemble the barrel and bolt assemblies into the receiver, be sure the indent in the curved end of the ejection port cover (Part #34) is locked ahead of the lug on the bolt carrier. The cover must enter the small slot in the top of the receiver freely. DON'T force it.
