FYI the owners handbook, Fiat P/N: 60306704 is available for £10.32
including VAT.

Can't comment on 1)

2) Could be a fuse problem.  I would suggest:

a) disconnect the battery -ve terminal and let the car stand for 15 minutes
to allow any sytem residual/stored charge to die away.
b) slowly and methodically pull and test every fuse on main and auxilary
fuse panels.

The auxilary fuse panel is located underneath the dash and to the side of
the main fuse panel.  To gain easy access it is best to remove the under
dash panel/oddment tray.

c) If all the fueses check out OK then there is most likely a connector
problem on the rear of the the instrument cluster.  I note that there is one
connector the feeds both the Turbo Guage and the Temperature Guage.

This is connector B and has contact details/wires colours as follows:
PIN-colour code- colour descriptions

1-CN-orange black
2-VN-green black
3-NZ-black violet
4-NB-black white
5-AR-lightblue red
6-A-lightblue
10-NV-black green
11-HG -grey yellow

If I remember correctly the connector has contacts that slide over either
side of a flex circuit which rises up over moulded central support ribs.
Remove the connetor and (1) gently clean the flex cicuit copper contacts (a
light rub with a pencil rubber is good at removing oxidation) (2) look into
the connector looking for broken or too greatly spaced contacts (the contact
oppostite faces should nearly meat together and be at least a close together
as 50% of the width of the flex circuit faces.  If the conact faces look to
far appart then they can be gently teased together.

Note!  I would suggest you remeove all the connector to the rear of the dash
panel and take the whole panel out, clean all flex connectors and check all
the mating connectors.

Finally, if everything else electrical is working OK on the car then I would
possibly tempted to go straight for the dashboard connections and skip the
fuse checks.  My circuit diagrams suggest the connector theory, however, a
full fuse check is always worth while.  If nothing else the fuse extraction
and reinsertions cleans the contact surfaces of any oxidation.

Report back on how you get on.

Nick /////