I just swapped mine in the car about 3 weeks back, took about two hours total, time will vary according to your experience level.

You're a little ahead of my write up schedule, here are some tips anyway.
Start be reading Broke's 5th swap pages, though he does it on a bench.
You'll need REAL snap ring pliers as Broke shows, plus the triple square socket he shows, don't even think about using an Allen wrench.
You'll need something for the 27mm cap nut, he's got a couple of suggestions, I'll add a couple nut from the hardware store with a 1 1/16" hex filed down to fit.
You'll need a jack, the stock scissors can work, you might need a couple of 2X4 blocks to jack the trans a bit both the relieve the load on the left mount for removal, agin to line the mount up during re-assembly.

At the bottom of page 2 he shows a special tool for the 5th shift fork, you pretty much must have one. I made mine out of a 6" long 1/4" galvanized pipe nipple from ACE Hardware. I cut down to the tabs with a saber saw, a hacksaw can work too. I had to drill out the pipe seam with a 31/64" (I think that's what it was, just a little bigger than the pipe ID).
Once in use it tried to thread itself into the shift fork and jam there, I hand filed it down a bit.
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On Broke's 1st page, 9th, 10th and 12th pictures, you'll see a rod with a spring on it, the 10th picture clearly marks it "Do Not Remove", he means it. The spring will have to come off, it'll be in the way, the rod MUST stay in place. The rod keeps all the shift forks lined up inside the transmission, remove it and you WILL have to open the case to re-install it.
Don't confuse that rod with the clutch release rod, Broke's page 1, 10th pic, he's removing the release bearing, there's no clutch pushrod underneath because he's already taken it out of the other end, he's working on a bench unit.
Your clutch pushrod will be under that bearing sticking out of the center of the input shaft, pull it out, look at both ends, one will be flatter than the other, near the end, put it back the same way.
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You'll also need the clutch cable disconnected and out of the way, a pan to catch the oil that will run out when the cover is removed, oil to refill.
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I tried to get clever and avoid the step removing the shift selector, no joy, it had to come out.

I raised only the left front wheel on a ramp, steered full left lock for two reasons.
One, I hoped with the car still on the wheels, brakes locked and trans in gear, I hoped to remove the large triple square nut without removing the selector. As I noted above, that failed.
Two, I wanted a little help from gravity to keep the selector rod in place by tilting the car slightly down to the right. It worked ok, I didn't drop the rod, still, that rod kept me nervous throughout, I kept checking and pressing it back in. I think it's spring loaded inside, it tries it's hardest to get out.
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A couple years back as I changed my clutch, I made this cut to the inner fender well, it also provided just adequate clearance for the 5th in the car job. If I was doing it again, I'd cut a little higher.

I made the cut out back when I did the clutch.

I remembered back to the days of the shorter 4 speed transaxles when there was room to get the input shaft clear of the clutch without lowering the engine at all, made it real simple going back in too.
I used to be able to change out a clutch on a 4 speed in 1.1 hours with air tools and a lift, pure gravy.
Along came the longer 5 speeds and there wasn't enough room to pull the gearbox straight out, the engine had to be lowered quite a bit, then everything had to get raised and re-aligned on re-installation, times doubled or more wrestling with it. A2s and A3s were even worse.

Once we started doing 5 speeds, we just had to deal with them as there were, I never did cut a customer car, just wouldn't have been right, but I did want to cut every one of them. I didn't hesitate to cut my own.

Without the cut, front, rear and left mounts would all have to come off, the drivetrain lowered, maybe even one or both axles, the left might get in the way, the right might pull and bind or worse, come apart.

Then, once the drivetrain is lowered far enough, that pesky selector rod will have gravity helping it to fall out and ruin your day, probably your whole weekend.

With the cut, only the left mount needs to come off, the drivetrain sags only a little and a jack can prevent that.
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You posted such a beautifully dimensioned pic of the 5th fork tool, I just has to make it, cost 2 bucks, took 20 minutes including time to mess up the tabs twice before I got them right. The tool detail I havn't yet mentioned was at the other end, I stuck a 3/8" drive extension in the other end, squashed it down in a vise, worked just fine.
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Oh, the selector rod only starts to come out when you're busy with something else, I think Murphy had a hand in that design.

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