Since we currently have lots of downtime, I wanted to tackle this.

How difficult is it and is there anything I should be looking out for while trying to change all these parts?

 

I have only done this job once so I'm sure others will have better advice but I can offer two suggestions. Do the PCV mod while you're at it if you haven't already, and be extra careful when torquing down the VC gaskets to ensure the rubber doesn't flare out anywhere along the edge. I had to reset mine and start over a couple times because the internal lip was moving around in the groove. In the end I got a perfectly uniform seal around the full circumference of the covers but it took a few tries. This may be the.result of one brand of VC gaskets versus another, I have seen comments here that there is a preferred brand. There are some other tips like swapping out studs for bolts on the SAI valves (if so equipped), and maybe if you can afford the downtime once the upper IM is off you'll have good access to the injectors so may be a good time to send them out for cleaning.

And don't forget you'll need a 12pt 8mm socket to get the VCs off.

 

Do Best4x4's pcv valve mod, a $7 part, quick and easy install, and will keep gaskets from leaking prematurely.
Make sure the coil bracket is bolted down tight, so they are properly grounded.
Save yourself the hassle and remove the upper intake manifold(6 bolts), to give yourself room to work.
A thin bead of rtv silicone on both sides of the valve cover gaskets, and they are torqued to only 6' lbs.

 

+1 on the injectors too.
They are $60-$80 for a remanufactured set on ebay.

 

@GoRoll If you have SAI this is twice as hard as it should be, But even then it is pretty easy just more cursing.

Get a set of wobble extensions from Home depot, they really help with the coil pack bolts.
If you have SAI you need a short 18mm Open end wrench and short 27MM open end, lots of penetrating oil and take your time. Watch the pipes if they twist they will crack and be junk.
Valve covers are 8mm 12 point

Other than the SAI it is a hour to hour and 1/2 job if the Coil pack bolts play nice, a magnetic 8mm socket would help

 

Is it possible to do this with the SAI pipes in place but removing the valves? I can't remember at what stage of reassembly I did the VC gaskets but perhaps it was before SAI went back on.

 

@ahab not in stock configuration, if you replace the SAI bracket studs with bolts you can, that what I did. The bolts are annoying to get started but you can pull the upper intake without removing the SAI tubes.

replace SAI studs with bolts

 

On the 2000 D2, are the coils individual of 4 or altogether as 8?

 

Two separate coils of 4 terminals each.

 

Are coil packs a wear items w/ a recommended replacement interval on these trucks? Some people say 100k but Id guess most don’t bother considering them as a scheduled maintenance item (at least I haven’t on previous vehicles).

I bought new plugs and wires to install next weekend - since I don’t have SAI, this should be a relatively quick job if I don’t do coil packs as well. However, probably makes sense to do all three components at once if the coil packs are something that should really be replaced.