classic motorcycle forum

I am restoring a 1980 xs850 midnight special, i got the bike from a friend who drove it into the ground, well as i was taking it apart to repair and repaint the frame i found some wiring and a lot of mechanical issues, i would like to know what the best way to 1. rebuild this bike in the most cost effective manor. 2. converting a shaft driven engine to a chain driven. 3. can i make a new seat since my previous one was destroyed by snow and the elements.