The cheapest option is to just get a different dial face, no need for a chip
http://cgi.ebay.com/Mitsubishi-FTO-Spee ... p1638.m122
This will give you a mph readout, your odometer will obviously still be in km. the 180kmph limiter is still there
If you fit a convertor chip, and keep the factory dial face, the needle will be on 60kmph when you're doing 60mph. you can get a face that reads to 180mph (the same as you have, but has mph written instead of kmph, it also has km reading
http://cgi.ebay.com/Mitsubishi-FTO-SPEE ... otohosting
This removes the 180kmph limit, and makes your mileage go up slower too