I wish I could give a recommendation from personal experience, but I haven't gone there yet. I've read several times that the Koni 84-1099 is a good way to go. Koni actually lists these as a direct replacement for 404s. I'm pretty sure a number of people have used them and been pretty happy with them. I think I'll be going this route when I get around to replacing the shocks.
There have been some Monroe shocks used, and I can look up some numbers. FWIW, the Koni's are the only aftermarket shocks I know of that are exactly the same fit as the originals, complete with sleeved ends that match the mounts and the bolts. The Monroes have to have washers to shim their sleeve lengths, or don't have sleeves at all, just rubber bushings. Plus, the Koni's are adjustable.
Bottom line though, the Monroes are half the price.
Rancho S9000's also work, but need just a little modification (washers to add sleeve length and the factory bolts are just a hair too fat). They are nice because they are adjustable. A little more pricey, and I use them on my crawler because they have a longer reach, so on a stock 404, maybe not necessary, but they are an option!
FWIW, I switched over to Koni 84-1099 shocks nine years ago and have never looked back. They are adjustable, as mentioned before, and rebuildable [if necessary]. Plus, they are specifically designed for the 404 and fit with no adaptations necessary.
I assume, but don't know, that you have the 'proper' springs that the radio box models have for their anticipated extra weight.
This photo was taken in 2000, before I refurbished the chassis.
Cheers . . .
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