Just an update. I got this reply back from Bilstein in case it helps anyone else looking at these:
"In the interest of clarity, I have pasted your questions below and written my answers beneath them. Thank you.
It looks like the 4600 front struts have 2 circlip positions on them. Is this correct?
I assume you are referring to part number 24-317894, this product does have 2 circlip settings.
I'm assuming the lower one is for the factory standard ride height and the upper one is for the factory raised ride height. Is this also correct?
The lower setting is for stock ride height and the higher setting will provide .7” of lift through spring preload. Maintaining the same ride height you have now will largely depend on how RAM lifted your vehicle from the factory. They likely used a slightly taller than stock coil spring to give you the lift instead of a taller setting on the shock. Ultimately you would want to lay down your OEM shock next to ours and compare the spring seat height to pick the correct setting.
Also, is there any difference between the 4600 and 5100 series shocks other than more ride height adjustability with the 5100 series?
The 5100 series is slightly taller than stock to accommodate for being used at the higher lift settings. Besides the length, the coating and the amount of grooves, they are very comparable products.
I'm leaning toward getting the 4600 shocks unless there's a reason I should go with the 5100 series. I frequently tow a 6500 lb trailer.
If your vehicle is stock ride height we would highly recommend our B6 4600 series. They are considered by most to be an upgrade in comfort and performance over the OEM system and provide superior handling and control when towing. At stock ride height they are our best riding and longest lasting damper. There is a lot of misinformation online that suggests our 5100 series is stronger, better or more heavy duty than our 4600 series. Nothing could be further from the truth. Both are made out of the same high-quality materials; the biggest difference is the coating and the fact that the 5100 is physically longer to accommodate for a lift."