Having done a quick search, I don't understand the post.

From the same supplier same quality plug, NGK IX

Set for Skyline = £44.50 For 6 plugs that's = £7.41 each

Set for Cossy = £28.98 for 4 plugs that's = £7.24 each

17p per plug difference..

You are allowing for Cossy = 4 plugs.
Skyline = 6 plugs I assume?

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