Huge thanks to the OP for posting this! Installed last night, took about an hour. Observations:
-Find a bench vise (it would be hard to hold the brackets by hand).
-Find a pole or board about 43" long to prop up the liftgate from the open tailgate. I was surprised when unbolting one side just how heavy the liftgate is (was unbolting one handed and holding the liftgate up with the other hand).
-I drilled out the old struts starting with a 5/16" bit and then had to open the hole on the factory brackets with a 3/8" bit so the threaded ball joint ends would fit.
-I did all cutting/grinding of excess threads with a Dremel w/ a cutting disc & sanding paddle (I think that is what it is called - it looks like a paddle boat wheel with 80 grit sandpaper).
-Follow pr0ject42's lead and order the slim nuts (item# 90257A045) from McMaster. I did only a small amount of sanding on the nuts and it fit perfectly once the excess threads are removed.
-Besides a drill + bits, dremel + grinding cutting bits you will need a 10mm socket or wrench/spanner and a 1/2" + 9/16" wrench/spanner (the standard sizes are for the strut joint end / 5/16" nuts.
The liftgate does open higher (for me that is definitely an upgrade) and feel like new.

was very, very happy!
Thanks again to all that came up with this, especially gabepari! If you are ever in the Bend, OR area look me up (even if you don't drink beer, I owe you a lunch at one of the Brew Pubs)!

Riley