You can get FRSt stuff for about the same amount, and in terms on reliability its a lot better, although there arent many places that map it. Thats what i would advise if you are on a budget.

Apparently the 3i pump isn't the same, there seems to be a lot of controversy over this though, i myself run a 3i pump at present......

For the wiring, have a look yourself to start with, as i think looking for yourself will help you understand it and then i can check how you've done

All the letters on the S2 diagram will have labels such as B, C, etc, cross reference them back to the 86-90 ignition diagrams, and then you can look the colours up for yours on the 80-86 ignition diagram