That will be the problem then:
I know others have had similar problem. But just to show it is not a new issue with modern parts. When I sent these pics to my dad he sent back some photos of him with the gearbox out of a Toledo at the side...
Oh yes, it's a bugger. I found a long tapered punch helps to enlign the holes but it's still a bugger. I've only ever done the job twice, all bushes, so haven't found an easy way that a landy mechanic at a dealer probably has.
I agree on principle that removing both is not a problem as you regain alignment whe. You refit. However from expiriance of swapping bushes on one and both radius arms. To get it lined back up and the bolts in requires a lot of prying, ratchet...
I can't remember the details sorry. But I remember it felt very secure with little effort. I had the same issues as you and I was trying to set modulation with a frost on the ground! Taking the fan off was the only way to get it hot, temp does...
Whys it hard to put back on? Remove it and wedge it away from the pullys with something, I used a piece of timber I had lying around.
No need to remove it completely off the car.
Found my post when I was a bit more dumber on p38 stuff.
Thread 'Sunroof- found where the leaks are but is there a part number.' https://www.landyzone.co.uk/land-rover/sunroof-found-where-the-leaks-are-but-is-there-a-part-number.381370/
As said, clean the 4 drains out first.
Then, open the sunroof and stick your head through or maybe lean over the roof from the outside and using a torch and a pokey thing like a pencil, examine in the area between the cassette and the underside...
Did this a while ago but needed decent rain shower to test it ...
Leak in boot fixed. It was the bonding along the top of the rear quarterlight window. Smear of sealant in the gap and she's dry again.
The hevac not only reads the pot value but also the current draw. If it's near the upper limit then maybe it pulls slightly extra current under certain conditions and trips the book symbol.