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I installed the full quad on my LAR8 a few months ago. They are both installed the same way. You will need a bench vice, barrel nut wrench, a foot pound torque wrench, and hand guard removal tool. The proper barrel nut wrench is very important for removal of the old nut and during installation to properly torque the new nut, and I would say is a must have. The install is simple, 1. Remove the stock hand guards with the hand guard removal tool 2. Remove the flash hider 3. Remove the gas block and gas tube ( I did not remove the gas tube from the gas block) 4. With the gun in the vice, use the barrel nut wrench to remove the old barrel nut and delta ring. 5 Put anti seize on the receiver threads and install the new barrel nut. 6. Torque the barrel nut to 35 ft. lbs. (I think it was 35 ft lbs. but the instructions will tell you how much to torque it). 7. Check the alignment of the gas tube hole in the upper receiver and one hole in the barrel nut. Make sure the gas tube goes through the barrel nut hole and into the receiver's gas tube hole easily. 8. Install the free float tube and use a level to make sure the free float tube is level with the upper's rail. 9. Once you are level tighten up the two screws to keep the half rail from moving. I used blue lock tight on my screws. 10. To install the gas tube I inserted a long thin wooden stick / dowel in the gas tube hole from the inside of the upper receiver, then i put the gas block and tube on the barrel. I then slid the gas tube over the dowel inside of the free float tube. This dowel guided the gas tube into the correct hole in the barrel nut and into the receiver gas tube hole. Before I came up with the idea for the dowel it was impossible to align the gas tube and the gas tube hole. If you take the gas block and tube apart this may not be a issue, I'm not sure. I tried to get the gas tube roll pin out of the gas block but broke my punch on it and it did not budge. The dowel idea will save you the time needed to disassemble and reassemble the gas tube and block. 11. Align the gas block and check how smoothly your bolt carrier engages the gas tube inside of the upper receiver. I did this by moving the bolt carrier back and forth inside the upper receiver to make sure it was a smooth engagement with no binding. 12. Tighten the gas block down, again I used blue lock tight on the screws. 13. Install your flash hider, and you are finished. 14. Oh, go to the range and recheck your zero. I hope this helps.