I've got an extra new in box (well new in little cardboard panel/bag thingy) VDO dual oil pressure with the right threads (M14 x 1.5 I think) if you think it might help solve your leak. Also I think you might be able to get a wrench on it by removing the panel behind the seats instead of going in from the top with a crowfoot wrench (which is a major hassle...
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