The rocker covers were shaved to clear cowlings (this mod prohibited the safe lifting of the engine using its rocker cover slinging points

You still lift them that way, you simply swop rocker covers 🙂

Full details of the mods are here

http://www.caa.co.uk/AANDocs/21819/21819000000.pdf

Though what this has to do with the VC10 is beyond me.

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