As promised, here is a year-by-year guide, as far as I am aware.
The pictures are of either my cars, or ones I have found on the internet. The ones of each model year may not all be the same car, as it depends on the quality of pictures I have.
There are people who are far more expert than me who may be able to correct me (RJ, I'm thinking of you), and some changes I'm sure were introduced mid-model year.
1976
(Feb) Launched. One-Piece seats, brown interior, old basic dash, no side indicator repeaters, silver thin mirrors, silver window trim, front nose-cone, 3 door only.
1977
As 1976 as far as I can tell.
1978
A-frame headrests and Volvo style seats
Black dashboard and steering wheel with extra air vents by centre clock, and knob for light controls
New door card trim
Black mirrors
(this is not the standard steering wheel)
1979
Wing badging becomes ‘Volvo 343 DL’
Front number plate moves up to front bumper
Revised dashboard and steering wheel
Manual gearbox
Side indicator repeaters
1980
345 5-door introduced
Thick plastic door mirrors
Revised font on boot badges and wing badges
Front doors gain diagonal interior door pull
1981
Wrap around bumpers
GL trim level introduced
1982
Revised front
1983
Revised dashboard & door cards.
Revised trim - tweed
360 GLT and GLS introduced
343 and 345 now both called 340.
(These are pictures of a 360)
1984
Window-mounted wing mirrors
Loses front quarterlight pillars
3-door loses rear air vent
1985
Saloon introduced.
1.7 litre engine introduced
Revised trim with piping around edges
Smiths dashboard instrumentation replaced (fuel light now has central yellow dot)
1986
Redesigned front and rear
(later in model year) Blue-red heater controls
1987
Revised seat trim, tweed
Rear wash wipe on all hatchbacks
1988
Wider side rubbing trim, approx 3cm.
Recirculation button disappears from heater controls
1989
Black window trim introduced
Rear wash/wipe
Rear third brake light
340 (no DL/GL) introduced
1990
Saloon discontinued, 360 stopped
GL gets contoured steering wheel and plush interior
GL gets wide side rubbing strips
Models are only 340 and 340GL
1991 (Mar) Ceased
Catalyser standard(?)
