Servicing your own classic is an easy and satisfying job, as well as that regular servicing will extend the life of your engine and increase the time between rebuilds and reduce the chance of breakdowns. All of the parts required to service the MGB are readily available and are quite cheap but it is important to buy good quality named components if possible (I had one set of points break and a duff rotor arm).
Classic cars need more maintenance and servicing than a modern car as there are few if none of the electronic gadgets. This does not mean that classics are pain and are always in the garage being fixed. The following is the recommended service intervals and maintenance schedule on a classic as given in workshop manual. These routines were written when car was new and being used as an everyday car so in the case of a classic being used as a second car or as a Sunday bit of fun then there these can be used as a guide.
Every 250 miles or weekly (or when you get the car out for the weekend)
Check the tyres for tread depth, cuts and sidewalls as well as the pressures
Check the wheel nuts or spinner for tightness
Check the engine oil level and top up to the required level if required
Check the fluid in the brake and clutch master cylinders, top up if required
Check the water level in the radiator and top up if required
Check the water in the washer bottle and top up if required
Check that all the electrical system is working light, wipers, horn etc
Every 3000 miles or every 3 months (also do 250 mile routine)