Okay... we need to clarify a few things here...
What year is the car for sure (there was no 2.3 in 1970; there was a 144cubic inch inline six in the early-to-mid 60s from Ford, which would be 2.3L converted to metric, but it's not the 2.3 we talk about in this forum (the 140 cubic inch SOHC inline-4 used in Mustangs from 1974-1993).
You also mention 200cc, is that supposed to be 200ci??? 200ci would be the 200 cubic inch inline six used in Mustangs throughout the first generation (including 1970) and again from 1979-1981 (though renamed the 3.3 because of it's 3.3Liter displacement using the metric system).
Not trying to ridicule here, just trying to help you out so we can point you in the right direction, if you're just mistaken in the year and it has the 2.3L 4-cylinder, then you've come to the right place, if it is a 1970, then you might get better help here:
Classic Tech | Mustang Forums | AllFordMustangs.com
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1976 Ford Mustang II Ghia: 302 with a 600cfm Edelbrock carb, Edelbrock Performer 289 intake, Dynomax Blackjack headers, 2.5" exhaust with Flowmaster Super 44s. RJS 11-gallon fuel cell, C4
tranny, chrome 16" pony wheels, fuzzy dice, brown vinyl half-top, and painted in the tackiest color ever (harvest gold, that's why I call it "The Goldenrod").
Also have a 2003 Dodge Ram (lightly modded daily driver/tow rig/office/dining room/home away from home/workshop... I call it "The Big Blue Dawg".)
4-lug Drum to 5-lug disc Rear Conversion 
