So I kind of got carried away, doesn't that just always happen!
Here's a list of what I replaced:
KMC Chain £6.98
Shimano 7 speed freewheel £8.49
VP square taper bottom bracket £9.99
Shimano fcm 131 chainset £17.99
Shimano 7 speed and 3 speed EZ Fire shifters/levers with gear cables £15.31
Acor headset £24.95
Shimano Alivio rear V brake £13.49
Clarks 72mm V brake pads £5.98
Took apart, cleaned and regreased front forks (free)
That's a total of £103.18 inclusive of delivery charges where applicable.
Because I got carried away I also added:
Charge Spoon £12.50 (second hand) thanks
@davester65
Savage 660mm DH bars £11.97
Ritchey pro Truegrip 6 £5
Elite Custom Race bottle cage x2 (one to house a tool kit) £17.98
Swapped better tyres from the wife's MTB (free)
So that's a further £47.45 so a grand total of £150.63

I did all the work myself so there were no labour charges.
So basically I've spent £150 on my bike that isn't worth £150! Proving its pretty uneconomic to refurb an old bike. But, looking at it another way I've spent £150 instead of spending £300+ on a new bike thus saving myself £150+

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And doing the work myself has been thoroughly enjoyable, Ive done things on the bike I've never done before. I borrowed a work stand from a mate who also had a pedal arm extractor tool and BB extractor tool. I also bought a chain splitter for £11.50 which I'm sure will come in handy in the future.
It's never going to be a "great" bike in modern terms, and I know a lot of the parts I've used are "budget" but I think I've shed nearly half a kilo, It will do me just fine for my ambling around, and giving it a brief test ride has been a revelation! The gears actually work - one click, one shift, the brakes work, the steering is smooth and taut again, the drivetrain is smooth and quiet, just need to give it a proper shakedown now, all in all very pleased

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