I don't have the means to make on up so I bought a brass fitting to do the job. What I didn't realise is that the thread in the crankcase is recessed, so my fitting almost didn't reach the start of the thread!
Anyway, I managed to make some measurements today. It was quite a cold day and I could only get the oil up to about 80 deg C on the ground. At 4600 RPM I had a pressure of about 3 PSI or 0.2 bar, which is within the permitted limits so no smoking gun there!
Any ideas on where to look next? If I had an excessively lean mixture that would give rise to higher temperatures but I guess that would also be seen in the cylinder head temperature as well as the oil?
