mixer tap spout

You can get right angled screwdrivers, even ratchet ones

Ah, you obviously missed the mole grips mention in the original post :) The bits I have are all 25mm and I imagine that's a standard size. I could do with 3 or 4 mm less. Looks like an angle grinder job

It will be an allen key. Mine are. Bloody modern rubbish. Bite the bullet, take best guess and cut an allen key to a short length. Or, blast it with WD 40 or something.

It's similar to this

Alternatively use a core drill from the outside and then use a long screwdriver, refit core and bodge with silicone sealant and gaffer tape.

I'm not quite sure from your post whether the screw has a socket for an Allen key, or whether it's Pozi.

However - whichever it is - I assume that you've got a bit which fits it? The bit is presumably hexagonal is section, to fit a normal driver? Rather than use a Mole Wrench, why not rotate the bit with a suitably sized ring spanner? If the bit is too long for the available space, grind some off the non-working end.

Chicken and egg. I think it's a pozi but I can't tell for sure because the bit's too long. Yes, it's angle grinder time. I'm guessing the grub screw has no effect on how freely the spout moves, and I'm now wondering whether there's anything I can do even if I take it apart

Did you even read my post?

I did, but it's not an allen key. It's either pozi or philips. My allen keys are shorter and there would be room for them if they had a pozi or philips head. Did you even read mine? :)

Well, thanks for saying taa for the effort Mr Pounder. I tried to help and was ignored. You just have to be a southerner.

If I remember rightly, the grub screw sits in a groove in the spout and stops it moving up and out of the fitting so, in principle, taking that out should let you lift it out (cack in the gap permitting)

In message , The Other Mike writes

To avoid this problem, I on a couple of occasions I've made sure that I fitted the tap 'the wrong way round', so that the grub-screw was at the front (and adjusted the handles to suit). Of course, if you do have to remove the spout (say to replace the O-ring), to forestall the inevitable departure and loss of the grub-screw, make sure that the plug is in the plug-hole.

If you don't want to be ignored, you should perhaps read the post before replying. It's not like it was long and rambling. Sorry and all that, but it's normal to thank one and all when the thread dies. If you want individual thanks you're probably in the wrong place.

Wow, that's what you call forward thinking!

That's what I thought. This thing has been stiff since the day it was fitted. I hoped it would loosen up in use but that hasn't happened

A spot of silicone grease (or other high-melting-point grease) should help. [So will WD40, but it's effectiveness probably won't last very long.]

I was once a Boy Scout, and still live by the motto.

Very difficult to get any lubricant in there. Because of the design it would have to soak upwards.