I believe I just answered my own question...? Seems the new brass fitting that comes with the replacement part is pre torqued, and all I need to do is remove the old fitting by sliding nut up the tube and removing compression fitting (easier said than done). Once the old fitting is removed, it's simply pushing air line tube into new brass fitting until it can't go in any further, and then pulling back.

 

Yes, you reuse the existing Voss connectors and keep the ones that came with the block valve as spares. I did look at the video above and see they recommend using the new fitting. The reason I like reusing the old fitting is that I am more confident of maintaining the old seal between the Voss and the airline than I am re getting a new seal - judgment I guess. If I have any criticism with these kind of videos is that it assumes everything is new etc.

The link below is to a gallery with a number of air system related files. At the bottom are three files specific to the Voss connector. One of the files is a MS Word docx that is actually a cut thru of a Voss connector.
In brief, you just unthread the three Voss connector airlines from the old block valve and then screw the three old Voss connector airlines back into the new block valve.
In other words, you do not disconnect the Voss connector from the plastic airline, you unthread the Voss connector from the block valve.

Link to gallery and a number of files re air system.
https://www.disco3.co.uk/gallery/thu...php?album=3802

Link to cut thru of Voss 203 connector (one ones on the valve blocks)
https://www.disco3.co.uk/gallery/dis...um=3802&pos=22

Link to all my galleries:
https://www.disco3.co.uk/gallery/index.php?cat=15405

 

Finished install of new valve block a few days ago. Front end was lowering every night for past year, got to the point where it was resting on bump stops. Replaced valve block and system seems to be airtight again. I am grateful for these forums, and will give back by sharing my experience. I used the advice of my previously posed Arnott Voss video and removed the old connection and used the new quick connect union. Removal was very easy. Push nut backwards along the air line and use a flathead screw driver to spread and remove the compression ring. I found my 2011 air line to be almost "brand new" after removal and wiping off with water and a paper towel. With the new valve block I simply pushed the line into the pre torqued Voss fitting until it hit bottom, and then I pulled backward with moderate to light force to confirm the lock. When you push in you feel an obvious connection (all jokes aside). Thank you for all the pictures and detailed descriptions in this post. Makes a DIY'er feel confident they can replace parts like this. I'd rate this a 3 or 4/10 in difficulty. Regards!