Perhaps you're burning yourself because of how many areas you seem to be working on at once.
Engine, suspension, 5-bolt conversion, interior, body work, etc... etc..
I think if you get it running First, it will encourage you to get it driving, then after you drive it, you will be more encouraged to finish the interior, or body work... etc..
I also keep a folder with all the inspirational pictures of carbon fiber cars, nice Z cars, and cool fabrication pics to give me inspiration whenever I start losing sight.