Just took a closer look at your pics. I have the same kit with the same item number. If you take a look at the 6th adapter from the right (one that fits the TDI glow plug hole), you will find that it does not have a threaded flare like the adapter that fits the Mercedes glow plug hole, which allows you to put an elbow on the adapter to connect to the gauge's quick coupler.

Per HF's site, if you search for item 93644, it comes up with the tester I posted in post #3, which is different then yours and mine. They must have changed the kit.

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I'm confused. You have the kit, it has the TDI adapter (long one, 6th from right). The kit also has the gauge/hose/fitting. Is there some fitment issue that you can't use the hose on the TDI? Do you need to swap out the elbow on the hose for a straight connector?

I bought the 93644 kit yesterday at the local HF for $20 and it is not the one pictured on the website, but is the same one in Diesel911's pic, so I think it's a bad pic on the webpage.

If push comes to shove, couldn't you simply unscrew the brass slip fitting from the steel elbow on the end of the hose?

The TDI glow plugs are recessed pretty deep and makes it is very difficult to engage the quick coupler onto the adapter. If you can get it to engage, it is even more difficult to disengage. On cyl 1#, it is not possible to engage at all. What will "unscrew the brass slip fitting from the steel elbow on the end of the hose" do for me?

If I modify the adapter to make it longer, that will do the trick. I may cut the adapter in half and thread or braze a tube between it. That should work.

__________________
85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Okay, I understand now. You want to extend the male quick connect portion of the TDI adapter to make it easier to engage the quick coupler. Then yes, it seems like brazing something to that adapter would work.

In an earlier post you said:

and then asked

Unscrewing the brass quick coupler would have given you the part you said you were looking for. It wasn't clear what you wanted that part for.