What's the best way to clean the stainless steel lid of the Daniel Boone?  I was thinking tide and magic eraser.  Is there a tried and proven method?

Dawn and warm water for the grease and dirt.  Bar keepers friend for the stainless steel.

 Depends on what the "dirt" it is. If it's oily and has traces of light smoke, pure Simple Green sprayed on then rubbed in and wiped off. Heavily cooked on deposits require a more aggressive approach such as

 Barkeepers as stated above. Barkeepers powder works better than the liquid. Use it with a SOFT scrubby, and only in the direction of the grain or polish marks. A stainless steel cleaner such as the one by 3M is

a nice final touch. It doesn't clean much more than fingerprints but does leave a nice oily protective coating- looks good and will burn off on the first cook.
 
 If the metal is scratched from inappropriate cleaning, there are methods to restore its finish..The key to cleaning the pits parts is; do not wait. It's so easy to clean-up a lightly soiled surface than one that

has been repeatedly baked on.   

I use Greased Lightening.
Does good job on grease and smoke.

Bar Keepers and chore girl for the Memphis Pro!

This probably won’t be popular but here goes. Let it show how much you love it and use it. Inside is a different story. Just my 
Never cared about how they look, rather how many people you made smile.

I'm not s big fan of cleaning them either on the outside or inside.

 I can side with  not cleaning the outside and simply a quick grate scrape inside. That's how I was for years.   I wanted my pit (only 1 @ the time) to mimic the many pits of the Southern US. Usually brick pits

coated with goodness inside and out. Right or wrong, in my view, that equated to good taste.   

I'm not s big fan of cleaning them either on the outside or inside.

I am getting that way. Only thing I do now is wet cloth to remove the soot inside about 2 or 3 times a year.  Barkeepers Friend works but results do not last long. If you go to RT's website and watch their cooking videos, they don't clean theirs either, just the grates.  Kinda like the scar on the face of the old swordsmen--a badge of honor. 

Memphis Pro & Bar Keepers Friend

Proof that Bentley does clean stuff, I like it. I prefer the powder with a blue scotch brite sponge personally as it seems less risk of scratching. Funny to see this topic today after I spent a good hour cleaning the Summit charcoal grill this morning.

You all got me thinking. Though I do not anticipate further cleaning of my 590, I did clean the lid edges best I could with Bartenders Friend, and scotch taped the pit edges that it sets on. Then applied a trial run of high temp gray permatex to the lid on one edge and closed the lid against the taped edges.  If the sealant holds well and the scotch tape will release properly, I will do the remaining 3 edges. If happy with the results I will brag to the masses. If not happy I will clean it all off and let you know.  The big problem is to get all of the black soot, and creosote off of the lid edge.  Not an easy task. Ruined 2 whole towels in the process.  Tomorrow will try the separation test. 

Permatex did not stick well to the applied side, partly due to sticking harder to the scotch tape on the other side. Sooooo--- I reaped and smeared grill cooking spray on a rag and wiped the scotch tape with it and recalled.  We shall see.  Still have about half of the lid to do if it works.  Or will need razor blade to remove the silicone if not.  Fun experiment.  More to follow.

Permatex did not stick well to the applied side, partly due to sticking harder to the scotch tape on the other side. Sooooo--- I reaped and smeared grill cooking spray on a rag and wiped the scotch tape with it and recalled.  We shall see.  Still have about half of the lid to do if it works.  Or will need razor blade to remove the silicone if not.  Fun experiment.  More to follow.

Bar Keepers leaves a minutely fine powder behind. If the silicone was applied to a surface cleaned w/ Bar Keepers and not further cleaned w/ a solvent such as acetone or alcohol, that would explain the  silicone not adhering. Just a guess on my behalf.

Okie, try just putting the silicone on the lid and closing it on waxed paper.  That's worked in other applications.