In article ,
Bert Coules wrote:
but to create a flat, even back to the hole, at the correct depth,
almost invariably escapes me.

You don't need to. Simply make it large enough and slop in a dollop of
quickset mortar. Wedge the box in place until it dries.

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*Real women don't have hot flashes, they have power surges.

Dave Plowman London SW
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