trevtherev

I can only assume that the caliper casting are of an aluminium construction and the coil inserts give a much stronger thread form.

Having just had a look, I see both my calipers have helli coils, so I take it that's normal, or the previous owner had been a bit OTT with the sockets.
The size bolts I have are 12 mm x 35 mm x 1.75 pitch flange head bolts. The rating I have is 10.9 Although I believe the normal rating is 8.8

Just saw your post, will have a look tomorrow and see what size the threads are. I noticed the set I've just bought had been helli coiled, so maybe someone else can say if it is normal.

I had rubbed my fingers raw trying to fit that belt and then setting the tension. To say I lost my temper is an understatement. Make sure you get the cam locking piece fully inserted between the cam wheels. Trust me they do line up, I started to chase after, maybe if I set the cam wheels slightly off it will come back. I found it was the slack I had in the long right-hand side of the cam belt that threw it all out. Eliminate that, and the marks in all three places line up.

Hi I had very similar prob;em and for the life of me I couldn't get that long r/h side tight, so the cam wheels lined up the crank was out by about a tooth.
Hope this makes sense: I fitted cam belt around tensioner, water pump and around both cam wheels (Locked). I found by sliding on about half the width was workable and with the bottom of the belt pulled like crazy to get the r/hand side tight and on the crank pulley. I set the belt back onto all pulleys and tensioner etc, and it lined up.

If you feel you can replace the bearings, even by asking at a local engineering shop or even at a garage. I'd say have a go. I used a cheap bearing press set off the 'bay' and found it far easier than I expected. You also get that sense of achievement which money can't buy, apparently. But I appreciate not everyone feels confident to attempt some repairs.
Whilst, I can't claim to clock up a lot of mileage, the front bearings were a constant advisory on my MOT until I replaced them last year. Since it says slight play, maybe It's something for another day further along the road.

I had a similar problem with both my seat belts, and after I bought a second hand set of belts, they still seemed less than snappy to return. I saw advice to spray furnisher polish on the belt, but I wasn't keen on that as a solution, so I removed the belts from the car and pulled the belts fully out and removed the belts from the winders. I used clothes pegs to stop the winder from winding back. I washed the belts and allowed it to dry and refitted. Still, they seemed a bit slow, so I removed the belt again and added a couple extra turns to the centre, which made a heap of difference.