Sorry for the delayed response, I was on travel and just got back to my laptop.
As to your question, the answer is yes.....we think.
Right now there are 2 schools of thought:
The first school of thought is that you can drop the SC engine right in, swap the engine wiring harness over, and for ease of swap, the engine bay harness as well. (This is not required, but you are going to have to wire in the SC intercooler pump). In theory, you'll need to add the SC cooler to the radiator stack, but as one of the posting members can attest to, it's fairly simple and the LR4 was already set up to do it...even back in 2010. (or at least 2012 as that was his year model). At that point, you'll need to use the SDD tool....yes, the SDD tool, GAP won't do it, to reprogram the security key to allow the SC engine PCM to be added even though it has a different VIN coded to it. (Unless of course you can find someone with a ****** ECM and it'll auto program the first time you plug it up, but non of the aftermarket "eco companies" are willing to do it, so it'd probably have to come direct from JLR for a small fortune). In theory, once you're at that point all should be well and good after you update the CCF to reflect all the engine differences. Let me just stress that aside from one person on this forum chiming in that he has indeed accomplished this, and jlrmongoose (where I got my SDD tool) stating it's possible, no one has actually completed it yet. This is the path that I'm following, I have just decided that I really want to build my engine a little stronger and better than stock, and it's slowing my progress down a little....ok, a lot.
The second school of thought is that you'll need to swap all of the main security key modules from a donor RRS SC to your LR4. (Engine PCM, BCM, ABS, Instrument cluster, KVM, CJB, I feel like there's one or two more, I just can't remember them off the top of my head) Obviously, this is a little more intrusive of a swap, but to date, the only way we've proven it can be done....sorta. I say sorta, because the gentleman who accomplished this is fighting with the RRS hardware as the system still thinks the adaptive dynamic suspension system is installed...which it's not...and it's giving him a suspension fault and while the engine runs fine, the suspension is sitting on the stops and won't work until it can resolve itself. He has disabled it in the CCF, and has been working very closely with GAP to reprogram/update his modules, but this is the last hurdle he needs to overcome to be 100% up and running. That said, there's a chance either his ABS or BCM may have some water damage and may be faulty, hence the fact it won't take the new configuration. He's still working to resolve the issue, but is stuck working in very limited bursts due to schedule issues.
So the overly long winded answer to your question is yes, in theory, just a few mods should transplant the engine into the LR4, especially if you buy either a low mileage running engine, or a completely rebuilt one. I bought a used running engine, "with a slight knock" which turned out to be a spun bearing...so that's why I've had to tear mine all the way down. I have all the parts to put it back together stock...but where's the fun in that? if 510HP is fun, 800 should be REALLY fun!