Daughter on holiday for a week and car dealer serviced the previous day so while she is away I was able to spend some time on it and try to install the full size dip stick.
Further comments to follow but also trying out instructions to upload images so here goes.
Well that should be the images uploaded but it's not what I expected.
The installation itself is very basic, but access is another matter. I thought that it would be a lot easier if I removed the air hose between the air filter and the turbo as it is the obstruction. However, I found that there is a branch of that hose which is fitted with a particular type of hose clip which appears to require a specific tool to loosen it. (hopefully there's an image of that clip uploaded above) I was unable to loosen that clip so struggled on.
I initially cleaned the threaded hole with WD40 as suggested by Paul and wound the bolt in and out.
The technician's dip stick was obstinate. One of the clips broke off. I eventually managed to pull it out by looping strong string through it's handle and heaving. The indicated oil level was only covering the ball on the bottom end. I reinserted the dip stick to check, same result. It was easier to remove the second time.
Having eventually managed to install the dipstick tube I checked the oil level indicated on the new dip stick. It was level with the "low" line. I didn't expect it to be level with the "full" mark but was surprised to see it so low.
The electronic indication on the dash display showed Full.
Edit: Well the images are there. I thought I had resized them all to 640 x 480 but I must have only managed that on the first one. Never mind.
I'll have to keep the instructions to hand as I don't think that I will be able to remember how to do this image upload process.