Where to start?

I say start with anything. Sitting and staring won't get you very far.

It took me 9 years to do 2 full restorations. I always did one thing a day, no matter how trivial. It lead to one car being finished after 1825 days, and the other one 1533 days later.

It's hard to get motivated looking at the big picture. Breaking the job into smaller projects then completing them, will give you the motivation you need to keep up the pace.