bringing my schwinn back to life

i commuted on gas bikes for three years. when i got into them there wasnt this level of interest or support. i purchased a scooter alittle over a year ago, and my last bike sat in my hobby room unused. just before i put her up, her clutch was slipping. so im going to clean the clutch pads and clean and blow out the gears and gear case, and relube the gears.
Question: what kind of gear grease should i use ?
also i plan to deck her out this time with a tuned exhaust, shifter kit, a generator and full light set with brake light and turn signals.
Question: should i get the shift kit BEFORE the tuned pipe? or does it matter?
Question: and most basic of all, i cant remember the oil weight and oil to gas ratio
Does anyone have experience with advanced electrical systems and the items needed for the setup i mentioned above? What about cleaning the carb and gas treatment for the engine because they have been sitting?

Any help would be greatly appreciated. i am new at using forums, so im not sure where to go to see replys.

well thanks for the advice. i fired her up today. but the bevel gear wont stay attached to the crankshaft. it turns out that this is what i originally thought was a problem with the clutch engaging. do you have any experience with the crankshaft components? the semicircular bond wont stay in place, so the bevel gear spins freely around the crankshaft transmitting no power. looking at the set up, i just dont see how these parts would wear easily, and anyway the engine is fairly new. i dont know if i need some kind of adheasive or what. i plan on ordering the gear, column bolt, semi circular bond, and round spring gasket. but what if its the end of the crankshaft that these parts attach to ?

dear mr. bean. lol. couldnt help it. epoxy is holding. thanks so much for the advice. got my new bevel gear , spring gasket, and key in the mail yeasterday. will use them if i have to. question. when i removed the column bolts, a spring gasket much smaller than the one i got in the mail was underneath. i also see two different sized gaskets offered. where does the larger of the two go?