Hi Elias,
As I previously mentioned, our Honda approved '87-'93 English Service Manual in the Members' Content area would be a great place to start. (Click "non Flash version" link for the manual.) 1-22 (Section 1, page 22 (page 30 of our manual) shows the MC16 wiring diagram. You will need to ascertain whether you have an '88 or '89 MC18 ignition though, as they differ significantly.
eBay in the UK is probably your best source for MC16 parts. There are often quite a few spares advertised on there, or you can always try somewhere like buyee.jp or jauce.com to buy from Yahoo! Auctions, but it can be rather expensive, and there may be items that they are not willing to ship. (Shock absorbers are a favourite... shipping companies don't like to send items filled with oil/gas.) Altenatively, I can put you in touch with an agent in Japan who I, and a couple of other forum members have used, if you PM me. (I may be a bit slow to answer any PM's at the moment, as I am away abroad, and not on the forum much right now.)
There is actually an MC16 frame with NOVA (importation) document for sale on eBay right now, and I think [although someone else will have to confirm] that CBR400 NC19/NC23 front calipers are the same as MC16, and you can find those easily on eBay too. In fact, there's a LHS and RHS caliper on there now at £20 each. Again, someone else will need to step in and help you out as to whether they are actually interchangeable though.
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Andy.
NSR-WORLD.COM
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