First off, I wish I had one of those. I’ll have to take it off the car hand have the car immobile during the process. I have a spare IRS, but not an IFS. 
I concur with Geoff. put it in as a whole unit. it will be alot faster. You will need one of these to support the engine.
I noticed the safety wire is missing. this is something that you’ll want to do. if you don’t know how, I did a video on my YouTube Channel Jag Mods
the engine mounts are on the IFS the two bunny ears sticking up at 45ish degrees facing each other. incase you weren’t aware. I’m not being smug, just trying to be helpful.
The video is “How do you lock wire” safety wire is doable. Not easy but doable. I’d probably put the rotors and calipers on while its out. Lockwire will be easier. If you decide to lockwire once it’s installed, then you’ll do it before you put the shock in, and bolt up the sway bar. You’ll need the room. You’ll just turn the hub assembly to full lock to get to it. Engage your safety squints, cause you’ll be dealing with a long piece of wire.
If you must do it in pieces, the springs are the place to start, require a special spring compressor; which I haven’t been able to locate. Well truth be told, I did locate one to “rent” from the North America Jag Club, but I needed (wanted) it now. I didn’t want to wait for months.
After purchasing every configuration of spring compressors, and unable to locate an off the shelf spring compressor that fits in the required space and compresses the spring enough to remove the the spring without fearing for my life, I made one.
Side Note:
A trolley jack really isn’t an option, unless you have a 900 pound neighbor to sit on the sub-frame. while you remove the springs.
The bottom plate and spring will come out as one; oh and the spring will no longer be compressed. However, the springs do come out with ease. Getting them back into place? Well, that’s a different story.
The primary issue is getting everything to line up while compressing the spring. I’m referring to the bottom spring plate to the wishbone or A-arm. I made guide rods to run through the bolt holes in the bottom spring seat / plate (I don’t know what it’s officially called) and screw into the holes of the bottom A-arm / wishbone. it worked, but did require some percussionary guidance.
next you’ll need one of these, a ball joint separator.
There’s no guarantee that the ball joint boot won’t get damaged. So have a spare just in case.
The rest is just easy peasy unbolting. Keep track of where the shims came from. As my mum would say, put it back where you found it. The shims are extremely important to maintain proper alignment.
All that being said,
I think it’s going to be whole lot easier and safer to put the whole unit in as one.
for whatever that’s worth.
m
