Here is a link to a vid of my Yamaha R5 Rat bike. I bought a lot of 4 bikes. 2 identical 75 Yamaha RD350s, the rat bike in the vid and a DS7.
I put DG pipes on the Rat plus MotoCarerra rearsets. It has Dyna Coils, electronic ignition, fully adjustable drop down Z-bars and a K & N filter with Y pipe intake. About $1000 in parts but you would never know looking at it. I love riding it. People hear it coming and look at it like "WTF is that?!" It runs great as you can probably tell from the vid. I spent a ton of hours pulling the carbs to get the jetting right.
1970 Yamaha R5 Rat - YouTube