Hey Cruisingram. As far as the porting it is a fairly easy way to improve the breathing of your plant. The trick is not to take off too much, just clean up the rough castings and match the intake runner mouth to the carb boots. Also consider lapping the valves. These are two inexpensive ways to sneak a few extra ponies outta your motor.
Oldkawman has some pics and pointers on his site. Check it out here.
www.oldkawman.com/
Cheers-Colin Firth -Ontario Canada
'77 Kz 650 Custom - (Miss July on 2006 Kzr Calendar,) Newest rebuild includes Wiseco 810 kit, Kz750 cams, Kz750 intake valves, 750 GPz springs, Ported head, WG Mikuni 28's, Velocity Stacks, Dyna Ignition and coils, MAC pipe, 14 tooth sprocket, going back to original '77 Moon Dust Silver. Goal is to have a stock-looking bike that will tighten up any loose dental fillings off the light.