Don't give up.
I fitted a alternative unit which didn't need the removal of the distributor but the wiring should be the same ( hopefully )
The small earthing wire needs to be refitted as before prior to taking the point off.
The Black wire from the electronic unit – attached a male Spade connector to the wire once fed through the distributor grommet & connect to the female connector for the wire which goes to the –ve connection of the coil / tacho. You would have removed this connection when taking off the original wiring as the black goes to a spade connection then the wire extends onto the coil. You only have to connect the new wire to the spade connection in the wire.
From the Ignition switch inside the car, trace the white wire which is the 12 volts switchable supply & can be found easily without removing the Steering Column cover – place the scotch connector to this wire & a length of wire into the other side of the scotch connector to run the wire to the red wire of the Electronic Unit via any blanking grommet in the engine bay. I used spade connectors to allow easy connection of the wires & removal if required.
Depending on how you want the wiring to look – I fitted cable protection sleeves to the 2 wires from the distributor so no coloured wires were visible giving an original look.
All the weights & springs should be kept as you are only replacing the 'points' part of the distributor.
Plenty of people have fitted the Accuspark unit so there should be a few more responses in the next few days.
This is why this forum is so good - advise is always freely given.