The first thing to do is gather up a couple more CB160s for parts bikes. Since you have a fiance, get them broken down and into tubs, crates and boxes as soon as you can and she might not notice them. You are doing it right in that you have a nice running stock 160 that you can use in conjunction with your project. The first thing I would do is pull the forks off the blue bike and strip them down and make them perfect. Then I would paint the triples to stock and swap out that front end with your street bike and put in some tapered rollers. That improves your street bike and gives you a good set to work on for your project. That is the pattern I would follow throughout, with rear shocks, brakes, cables, electricals, tires, etc... At the end you will have a nice clean stock bike with period improvements and a project bike that is starting from known usable components.
I had a racer buddy that was getting married and he made it clear with his fiance that if the choice came down to new furniture of new race tires, they were getting tires. He raced for another 30 years and 20 some national titles even a bit of AMA Pro 250 GP. They are still married.