Well crap Ryan. They went and updated the instructions finally. And actually managed to make them worse if that was possible!

Which I didn't think it was...
Not sure when these were redone, and it has been about two years since I even looked at a copy. Since they'd been virtually the same for the prior 20 years or so, I only check now and then. Hoping to see an update clarifying the spring thing.
And those I saw could have been an older copy for all I know, but I think I pulled them out of a box at work.
So come on Warn! Get it together after almost 50 years will ya!
Sorry Ryan. Good products generally and I like the people. And some of them have been friends for many years. But I've literally been complaining about the instructions since the late 80's any time I thought I had their ear. Which apparently I didn't...
In the drawings in your link, they act like the only factory lockouts were from Warn! Pretty arrogant I would say, considering that just as many trucks being changed over were using Spicer hubs as were using Warn, if not more.
They show a diagram that makes it look like Warn has been the supplier to the OE's since the beginning. Which they were not. And that the only time you need to worry about the spring is if you have drive flanges. Which certainly was not!
They do hint to remove it of course, but not in so many words and the diagrams don't indicate that very well either. It's there, but you practically have to divine it with intuition.
I can see where they might think that, since you remove the spring with a drive slug, anyone should figure it should be removed with a lockout too. But what if the lockout in question doesn't look like the one in their diagram?
They did become the OE supplier of course, but it was not until the very late seventies or early eighties that they replaced the Spicer hubs as the factory lockout.
Apparently anything before that no longer exists in their minds. Especially if it can net them a few extra sales because they were not clear in their instructions.
And on top of all the other crap, they still refuse to even mention a spring in words in the text. Even though, from the very beginning of people swapping in Warn lockouts (late sixties maybe?), the spring thing has been
THE issue causing trouble. I think I saw my first spring-caused failure in the late seventies.
For all those years, it's been one of the single most common product installation mistakes around.
If you were the cynical type then, it would almost make you think they want you to destroy your new hubs so you can buy another one. Must be the sales department managers way of doing business. Same reasoning I suppose, where they justify charging for a single hub about 80% of a pair.%) I'm sure it does cost them more to sell just one, and yes business is business, but it's still cheeseball business in my book. Not everyone needs to replace two of them at a time. But for only 20% more, they know you'll take the bait.
So yes, as Justin said, it does "say" to remove the old stuff. But they make you interpret what they mean when you're not really familiar with the product to begin with. Not everyone is going to realize that the spring is part of the old assembly
ONLY, and has nothing to do with the new stuff. After all, it's not a gear, right?
Factory locking hubs are like a Chinese puzzle the first time you open them up. But once you know them, everything seems obvious. Before that, not so much.
Apparently it seems too obvious to Warn to even bother detailing it in their (otherwise very nicely laid out) instruction sheet.
But you would hope that after hearing complaints for so many years someone would have actually thought it was important to us out here.
While they never actually say to put the spring back in ("remove the old hublock") and they did say to take all the old stuff out, they don't make it clear that a hublock might have the spring. And the spring was only in the old stuff, but not in their pic.
Sorry you had to run afoul of it. Maybe there needs to be a permanent article here on the forums, listing all the easy little product pitfalls that we should not run into, but still do. Not everyone will read it before doing lockouts of course, but if we can save a few the grief, that would be great.
Maybe I can get us to mention it on our website instead. Not the same, but worth a shot anyway.
Good luck. Hopefully it's all in one piece and not too much in the way of aluminum debris is inside yours.
By the way, have you taken yours off yet? Curious what you end up finding.
At least it doesn't take much time to find out. Lots of hand-cleaner afterwards sometimes(!), but not much time.
Hopefully it's ok. And like mentioned, you can drive the truck even with them removed. Takes a few extra minutes to cover the open hub with some duct tape or (as I once did) a baggie with rubber bands.
Works great until you need four wheel drive.
Paul