Can anyone confirm that a 5J x 14" steel wheel fitted with a 175/65R14 tyre will fit in the wheel well in the boot such that the boot floor board/carpet still fits properly?

I'm pretty sure that's the spec of the standard spare, so yes, it will fit.

Factory spare is 167/70R14. Slightly narrower albeit by only a few mm, but is it enough to cause the boot floor carpet to lift slightly if the 175 tyre is used?

Edited 9 October, 20169 yr by ronime

Ours has 165/70 R14 for the spare.

The thing to bear in mind though is the fact that the toolkit that comes with it stick up a good 1.5-2cm up above the height of the wheel itself.

The wheel you mention would probably fit under the boot floor fine on it's own but possibly not with the toolkit insert fitted.

I bought a standard (full size/14") Citigo steel wheel and tyre off ebay, and bought the jack toolkit designed for the spacesaver from Horton Skoda. I used a Stanley knife blade to remove a quarter-inch sliver off the expanded polywhatever toolkit holder, and it then fitted perfectly in the spare wheel. As long as you align the kit in the right direction, the tyre and tool kit are at the correct height, and the toolkit provides extra support for the boot floor, without lifting it. [2014 Skoda Citigo Greentech Elegance] 

Edited 11 September, 20178 yr by allanhodgson
To indicate the diameter of the wheel.