Think the alternator has packed up and no charge so everything has slowly packed up

Hi.

The combination of circumstances is quite unusual. The only sure thing is that there is a major problem concerning the electrical system.

To troubleshoot the electrical problem start checking the battery ground cable, a bad connection in there can cause collateral problems in different areas of the electrical system.

On the other hand test wiring from injection, starting from injection switch located in the steering column. Check wiring from injection to electronic distribution, wiring to cooling fans and check if the injectors are getting power.

The unusual thing is the engine quitting slowly on a thirty miles trip. wiring problems will cut power to distribution or injection, and usually cause the engine stopping suddenly or malfunctioning from start.
I have the suspect that the electrical problem may have caused some important part to stop functioning, and may have collaterally damaged the engine.
If for example the fans quit, then the engine may have overheated. If the fuel pump failed, then there will be no fuel pressure.

After what happened, not only the electrical but also the engine must be tested thoroughly.

Below the wiring diagrams for 95 Legacy, click on the picture to enlarge. Please let me know if you need more help or technical documentation.

Could be bad voltage regulator. Usually they are built in the altenator.
You could have a bad main engine relay, so check that as well.