[SpectorV]

well if its a 99 up manual buy a dallas speedcal from dallasmustangs.com i have had one for over a year maybe nearly 2 and its been great, it is said to work on autos but not sure so ask them first. if not you will need a chip. for pre 99 you can only pop in a 23 tooth speedo gear and it still wont be right, if its a manual you can pop off the tial shaft and put a diff drive gear to match with teh speedo gear you choose and get a correct reading but not sure which gears you want to get.

 

[SpectorV]

it will still be off by like 7 mph

 

[SpectorV]

is it an auto or manual? not sure if it works for autos.... or pre 96s at least. its not hard to hook up pretty quick actually but i would not use the connector they offer for the all time power it kept comming lose on my car just use a sodering iron or something better than the little snap no connector they provide.