I'm wondering by what you said? I've seen people use the 5100's from the Tundra's, along with the longer coils on this model 4runner.
That being said is the 07 Tacoma struts really that much longer?
I haven't took the 4runner struts out yet so I'm not sure?
Yeah, they're quite a bit longer. With a spring mounted in them that will leave them with their proper range of motion, such as the taco spring that comes with them, it'll give you a ton of lift in the front.
I had two of the same struts in my garage because I got them free at work, and I had the same idea. After I did some research on them, I never went through with it.
If the taco spring will seat properly against the 4Runner's top hat, then technically this strut assembly will work, but it'll probably the equivalent of installing the adjustable 5100s on the extreme perches resulting in a lot of lift and severely stressed ball joints.
If they worked, there would be at least a handful of people on here doing it considering their relatively high availability, but I'm not sure I can recall anyone who is currently running with those struts from all of the build threads I've read.
The end result is achieved using an assembly with either a preloaded or larger spring but the same size assembly (toytec spacers, and harsh ride) or a normally loaded spring with a longer overall assembly (low range spacers, and more similar to factory ride, but hyper-extended ball joints).
Assuming your struts are the same as the ones I had in the garage, then this is a much longer assembly. Somewhere in the neighborhood of three inches if I remember correctly. It would result in way more lift than you want to get from a strut alone because on a truck with enough ball joint problems as it is, you'd be a ticking time bomb.
Edit:
The guy before me posted that awesome picture giving an idea of how much longer it is. You can probably get the frankensteined assembly you have in mind to physically bolt into your truck, that's correct, but when you see how far down it pushes your control arms to accommodate this long assembly, you'll see you're new limiting factor is no longer the range of the strut, but now the ball joint angle. You may max out the ball joint before the strut is even extended. Testing that ball joint while it's actually on the road is scary.
To go that route, you need to be looking for new cross members to drop the lower control arms, longer knuckles to raise the top ball joint, and you're now way outside of the $100 bargain you're anticipating.
