I see reference to a kit that use to be available from SiCo Developments. The old url is:
https://www.sico-developments.co.uk/...box-conversion. But that link is no longer live.
So I checked the Wayback machine for past versions, and found one cached copy from 2015. The kit is described as follows:
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For sale is a conversion I have designed to replace the standard IB5 that the fiesta ST was cursed with lol The IB5+ is prone to blowing up and not being able to take the power of the ST so this gearbox conversion was created to fit a gearbox designed to take the power.
This conversion is designed for approximately 150-200bhp cars and comes with OEM quality clutch replacement parts but paddle clutch options are available for an additional cost.
The parts in this conversion are:
Low mileage compatable MTX75 gearbox + new uprated slave cylinder
MTX75 gear linkage and gear lever
Painted conversion brackets to fit the MTX75 to the ST and the new gear lever to the ST
MTX75 conversion driveshaft parts
MTX75 conversion OEM quality clutch
OEM gearbox lower bracket
Fitting instuctions if needed
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