The (Naked) Australian RB1 headlight case is 61301-425-000 which is the same part as the CB900. It has small holes in the back and clips to hold the electrical connectors. 61301-MA3-700 is the part fitted to the RB2 with the fairing, essentially the same part with the back and clips removed.
Yes it is frame number 60 and in excellent condition, I bought a set of new pipes from Glenn Kirkham and it is currently getting a major service and caarby cleaner after being in a collection of 20 bikes.
A great ride bike and should be better once serviced because it had a bad miss at low revs.
Pictures before & after fitting new Glenn Kirkham exhaust system[ATTACH=CONFIG]861[/ATTACH][ATTACH=CONFIG]862[/ATTACH][ATTACH=CONFIG]863[/ATTACH][ATTACH=CONFIG]864[/ATTACH][ATTACH=CONFIG]866[/ATTACH][ATTACH=CONFIG]865[/ATTACH]