The Captain's right, although I've looked through all of my books, cannot find an oil pressure gauge for anything in 760
Here's a 780 in USA with the gauge but in °F, however the construction would be the same as yours
You'll probably have to buy a 780 to get the gauge out of it
{"embed-external":{"data":{"url":"https:\/\/cdn.ozvolvo.org\/uploads\/MCUD4NSF7VI0\/s-l1600.jpg","name":"s-l1600.jpg","type":"image\/jpeg","size":133229,"width":1600,"height":1200,"displaySize":"large","float":"none","mediaID":25691,"dateInserted":"2022-02-14T00:11:59+00:00","insertUserID":2359,"foreignType":"embed","foreignID":2359,"embedType":"file"},"loaderData":{"type":"file","file":[],"progressEventEmitter":{"listeners":[null]}}}}