Raki
VTM-sp00ky power
A standard minarelli manifold doesn't use this kind of connection between manifold and carb. You should either buy another manifold to fit most of do's carbs or you should buy a carb suitable for fitting with your manifold. I'd go for the first option, you'll have more choice in carbs, you can get a short/straight manifold and I believe the minarelli-way of carb-manifold connection is better than this.
About the gearing. Sure it is allways a good idea to get other gearing. Even if you don't change the gearing but go to straight gears other than the original ones, you'll lose friction and so have less powerloss. You can change the gearing effectively also. On your setup it maybe wise not to lower your reductionfactor of the gearing by a lot. So change either primary or secundary gearing. The 15/42 secundary seems like a good idea to me. You'll gain some topspeed and have the benefits of straight gearing.
About the gearing. Sure it is allways a good idea to get other gearing. Even if you don't change the gearing but go to straight gears other than the original ones, you'll lose friction and so have less powerloss. You can change the gearing effectively also. On your setup it maybe wise not to lower your reductionfactor of the gearing by a lot. So change either primary or secundary gearing. The 15/42 secundary seems like a good idea to me. You'll gain some topspeed and have the benefits of straight gearing.