The replacement harmonic balancer arrived today, I was looking out for the mail van, so yay!
With everything ready to go on the car, I tried a test fit and it aligned to the woodruff key and with a bit of a wiggle and a push it was on, no installer or pulley tools required (think I got lucky). I still had to go to AutoZone to pick up a Fan and Clutch Holder, figured it's a free loan and if it doesn't work I'll get some steel bar to make Lawrence's pulley holder, picked up some bolts and washers at Ace and back to wrap it up.
The holder worked well and I was able to get 150nm on the main bolt, then just under a quarter turn, don't think it's coming off. belts tensioned to a quarter twist, fans installed, cables tied and done.
Everything seems good so far from a short test drive, will keep and eye on things over the next few weeks.
Sorry, I was a bit too eager to take photos.

It seemed like a daunting job when I set out, but after doing it, I think it was one of the easier ones, nothing too scary.
Thanks to everyone in the forum, you help make owning the car a great experience.

AutoZone OEMTOOLS Universal Pulley And Fan Clutch Holder (my loaner didn't come with the bolts)
https://www.autozone.com/test-scan-a...der/547013_0_0

 

 

Sorry, I just realized I copied the wrong link to the pulley holder (blame the beer)

It was this one, the bolts secured through the larger holes
https://www.autozone.com/loan-a-tool...ool/409637_0_0

 

I'm not sure if anyone has gone through this but I thought it would be useful to put it out there.
I recently changed the drive belts hoping it would solve a solve a cold start squealing noise, but it turned out to be a failed harmonic balancer, which I duly replaced.
But I was still getting the squeal on cold starts and tried adjusting the alternator belt to resolve it.
I think the new belt had been stretched before the harmonic balancer was replaced while trying to silence the noise.

Yesterday I installed another new belt and this solved the problem and this morning I tried a cold start and no squeal.
So, I guess this is a warning to not overtighten new belts without checking the harmonic balancer first.
At least the belts are not that expensive, but it seems a shame to just waste one if it can be avoided.

 

There seems to be little adjustment on the alternator belt if it is out of length dimension from the official Jaguar stamped belt

I measured the official belt once before and have the figure somewhere but would only guess at this time

Someone once put on a out of manufacture cure date old belt off the store shelf causing squealing

 

The original replacement alternator belt was a Continental 5K980, which doesn’t seem to have a cure date, just ‘28’ after the part number.
It could be that it was older stock which may have affected it, although I am sure I over tightened it while trying to fix the squeal.
The Continental 5K1006 AC belt is working fine so I left in there.
The only available belt at O’Reilleys was a MasterPro K050385 which is the one that solved the issue