Unless you get really lucky and come across some great deals for replacement parts, be prepared to spend a ton of money. Browse Ebay and arcade specialty shops online to get an idea of prices. It adds up quickly. Just a rough estimate:
New Sideart $125 - $150
New 19" arcade monitor $200 (optional)
Control Panel $50 - $100
New CP overlay $40
New Trackball $50
Marquee $25
Bezel and glass $50 - $100
board set $50 - $150
Atari Power supply $50
Centipede wiring harnes $25
Misc (paint, labor, hardware, buttons, tools, etc.) $???
You could save on some items, for example you could use the existing monitor if it is in good shape, you could try to remove the black paint to see if the sideart is still under it and intact, etc. But still it looks like you will have to get lots of parts to turn it back into a Centipede.
Also, you must consider why you want to restore it. If you just want have a Centipede machine to play yourself, you can get an old beat up working Centipede at an auction for several hundred. You can restore that later if you so wish as time and money allow.
If you want to go cheep, you could just invest in a new CP and trackball, then MAME the thing into a dedicated Centipede and/or Millipede. I was gonna do this with my empty Centipede cab, but then I decided to go all the way and do a full restoration.
If you want the challenge of restoring an old classic, then you will need to invest lots... I mean lots of time and money to the effort. Also take into account your skill level and facilities. Have you worked on any arcade stuff before? Do you have a workshop or suitable garage area that can be used for the restoration?
It would be much better to start with a tattered or non-working Centipede than to convert your Street Fighter II that barely has any original parts left.
If you want to restore the machine and then sell it, it will cost more to restore than what you can sell it for anyway.
I am restoring a Centipede machine right now
http://forum.arcadecontrols.com/index.php?topic=57135.0I got this one at an auction recently, they did have several Centipede/Atari cabs there that were painted black and had a different game in them. But I decided it would be a lot better to start with the Centipede cab for the restoration effort.
I wanted the challenge of restoring a classic, plus I am restoring it for my own personal collection, so I don't mind spending the money and time to do a full restoration. It will be very rewarding I am sure.
I hope this helps you out. Peace, Love, and Joysticks...