The entire restoration myth has been promoted by various agents of satan, whose interests are antithetical to mine. This includes the following nonsense:
1. spending money makes it more valuable in direct proportion
2. "numbers matching" is absolutely necessary for it to be worth owning
3. auction prices always go up
4. you always get your money back on a sale
5. bottom-of-the-line clunkers appreciate at the same rate as 1-of-100 injected 1957 Belairs.
6. it's a sound contrarian investment (which will behave opposite conventional stocks, bonds, precious metals)

Before you spend any money, ask yourself "When it's done, will I enjoy it? Is it fast enough, with good enough brakes to drive in traffic? Or am I already looking for that next project?"
This last is especially common, and tragic. Someone wants a 1955 Chevy, and can't find a rough 2-door hardtop (like the one he had in high school) for under $5,000.
He buys a 4-door sedan for $3,000, then spends $30,000 on it, before remembering he wanted a different car.
The $2,000 he "saved" by buying the 4-door is a very small part of the project cost, and he sells it at a big loss and starts over.
Oops.
Don't be that guy.