Dear Robin, I havn't tried it myself but local Ford garage said you have to pour it through the 'level plug' which is a hexagon plug in the forward face of the gearbox.
This acts as filler & max oil level point.
Probably a squeezy bottle with a length of rubber pipe into the hole.
Please let me know how you get on as I need to do mine!! mjheseltine@hotmail.com
Thanks & good luck,
Mark.
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