Oooof. That game is in absolute shambles. I hope the game is a keeper for you because I don't think you could get your current investment back out of it. A new play field with a garbage cabinet so you'll want to buy a new cabinet. You're likely going to have to spend $300 in parts to refresh everything and does the display work? You're going to end up spending ~$5k getting this nice. I highly suggest you look at what you can buy a pristine one for and decide whether it's worth your time or not to do this one.
If you're the type that likes a project then that's cool! But in order for you to fully recover the investment cost (minus your labor) you're literally forced to do a complete restore. If it makes you feel any better I bought a Funhouse for $1800, spent $4800 total on a new playfield (paid someone to do the pf swap) and the cabinet is a 7 out of 10. No way I'd ever be able to recoup the total investment. I love the game and it was worth it to me.