155 70 R13 fitted today. Made a massive difference to the low speed manoeuvrability and the the driving dynamics.

£40 a corner as well - I got 5 tyres for less than the cost of 2 fronts on my daily. As an added bonus the spare now fits under the bonnet, but I don't seem to have a nut to hold it down in there - is there a special nut or is it just a case of finding something that fits and a large washer to hold the wheel?
The little drive I did in it afterwards was much nicer with these tyres, but it's not running quite right - it's fine with significant throttle or no throttle, but on light throttle it feels a a little jittery like it doesn't want to hold a constant speed. It also feels like it's running rich - there's a definite fuel smell, though it doesn't look like it's dripping anywhere. Could these be linked? I know nothing about this engine (will have to read the manual). It's not been driven much, and it isn't especially happy when first started, but when it gets going then it's fine.
The other thing I noticed was that on bumpy roads, and especially when not accelerating, the gearbox linkage was clanging quite a lot (like someone playing a triangle in there!). I know it's the linkage, because it goes away if I put my hand on the gear lever. Is this a known thing, and does it mean it needs adjusting (or bushings replacing or something)?