Finless MOVE ON MATE!!!
Look at cars, would you really be able to use a 33 year old cortina as a serious form of transport?
If you want a project to do and then look at then OK otherwise (or while you are spending all summer doing that) go on
Ebay or look at old bikes in bike shop and get something for now to get you out and on the road.
You may be in need of the gears as the last 33 years may have had some effect on you.
I know all bike shops seem to be filled with mountain bikes but look around and there are lots of road bikes to choose from.
You need to move with the times, bikes like cars have got a whole lot better. But I agree suspension is a waste of time. Modern 24 gear bikes are a joy to use and they will help you get back into it better.
£150 will get you a good spec second hand bike less than 5 years old and you will end up leaving the old one in the garden once you have got used to the way things have moved on.