I have done this job in conjunction to an overheat on my 2010 LR4.
As others have stated, it's doable but it is a challenge considering the unknowns. If you have skipped timing, you should be removing the heads to inspect for bent valves, stretched valve guides and damage to pistons and replace what's damaged with OEM redesigned parts. In my case, I had damaged valves and valve guides but luckily the pistons only had minor valve contact. Valve stem seal replacement and checking valve clearances (replacing tappets to bring the clearances to spec) is also a must otherwise you stand to burn or bend valves. The head gaskets would need to be replaced which requires thorough cleaning of the mating surfaces, new headbolts as they are one time use stretch bolts.
While here, you might as well do all the water components (ie cross over pipes, water pump, thermostat and other misc water pipes and connectors).
All in all, this is still an approx $2000 parts job plus tools (timing tools, proper torque wrench, viscous fan tool kit and harmonic pulley removal tool).
I'm now at 1.5 years and 15k miles since rebuild and am more confident than ever that I can do it again.