To replace the starter on a mk1:
1. Disconnect the ground cable from the battery.
2. Jack the car and use stands.
3. Under the car use a 14mm socket a short extension and 3/8 ratchet to loosen the 2 bolts holding the starter to the tranny.
4. Pull starter, spin starter.
5. Take off nut and remove positive cable.
6. Use small screwdriver, insert in small recess in plastic connector which will unlock connector and pull, separating connectors.
7. Spin starter to take off heat shield using 10 mm socket. Remove shield.
8. Using 10 mm socket remove the bolt holding the under car plastic shield so that the shield will flex.
9. Flip starter so that the larger end is down. Wiggle starter through and out.
10. Clean mounting area for starter so that it will make good contact. Check the ends of the wires to make sure they are not corroded.
11. Reverse to install making sure the wires are not stressed.
12. Reconnect battery ground.