The video seems to display squealing belts. If the alt belt is a little loose, that's probably the one making the noise. Tighten it and the noise should go away. However, the slipping clutch and not getting over 63 mph are not the result of a loose belt. I'm wondering if you got some incompatible parts as Kerry was alluding to.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.