you will also need an adapter to mate the 2 cases together. the bolt pattern is different from the ford to the chevy and is clocked differently. I am running into the same issue trying to mate a ford 205 to a NV4500 manual. same exact tailhousing and output shaft as the 4l80. If you have access to a milling machine you could cut a spacer/adapter from aluminum to bolt the 2 cases together then run a long style 32 spline input in the 205. thats kinda what my plan is anyways.
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