I've got 3 first gen LS engines in my personal/work fleet now. 2 99s with a 5.3 and an 01 with a 6.0.
I acquired the 6.0 this spring,I've has one of the 99s since it had 50k,it now has almost 290k on it. The other 99 is my beat up,employee driving,work truck.
The one I've had the longest gets 10000 mile intervals including filters. I have only used tough guards and Canadian tires motocraft rebranded filters which is a tough guard.
That truck hasn't ever had an engine problem. I put a new cam in it at 150k just to make it more fun to drive. The old cam had a wear scar that I could see but nothing I could feel with my fingernail.
Since then that truck got retired from duty and was just used as my father in laws farm truck. Didn't even plate it for a few years. This summer I had to bring it back. Got it fixed up from the various dents,dings and chain damage from pulling tractors out on the farm. I need it for my now ex as a second vehicle,4x4,just in case of emergency for her and the kids.
These trucks need nothing special. They will last for nearly ever as long as basic maintenance is followed. 10000 mile filter changes are nothing for a tough guard. I cut all of them open after use and I find nothing out of the ordinary. The flat spring is still springy,the anti-drain back valve is still pliable.
Guys change their filters way to early. Cheap insurance is a joke. An filter gets better with age. It filters out smaller and smaller particulate until it's clogged.
Unless an engine is filled with mud it takes a whole lot of particulate to clog a filter.