W123 Diesel Transmission Line
 

The passenger side hard transmission line sprung a leak where the clamp holds the line to the bottom of the oil pan. Duck Tape didn't work. I will need to replace the line. I contact Mercedes Dismantlers in CA and they have the line for $50 + shipping to RI.
Some questions about the job. I traced the line and it seems to terminate at big bolt into the side of the transmission. I am going to guess that this is some kind of banjo bolt. Am I correct that this is what I think, that this line terminates there. The bolt is right near the exhaust pipe.
Will I need some kind of new washers/gaskets on that end? Are all these parts "dealer only" (I'll check with Phil after this). The job "looks" easy but is it really? I do have to do it on jack stands because I don't have a lift yet. When I change this line I am also going to drain the tranny, change the filter, and drain the T/C. I plan to refill with Synthetic and about 16 oz of TRANS-X from CRC. Roughly how much fluid should I put in before fine tuning the level. I am thinking about 7 qts but I want to be careful about overfilling.
Today, I tried to patch the line with duck tape which didn't help much at all. I put roughly a QT of Dex III in since the level was low from the leak. The transmission seems to flare a lot less than before. I don't think the level actually got down to where the trans got destroyed.
After all of this, would I be better off taking it to a transmission shop and let tham have at it or is this trivial and am I just getting too nervous about nothing.
Thanks for any and all advice.

You need to use genuine Mercedes Benz duct tape!!! But replacing the line would be cheaper.

I tried that but all them damn goofly little stars sticking out chewed up my fingers.

You might talk to a hydraulics shop about repair options for the existing line. I'm sure that bad section of the line could be cut out and replaced with a compression or flare fitting or even flexible hose. You would have to move the clamp a bit, but that might cheaper than replacing the entire line. Replacing the line is not difficult, but $50 plus shipping is not cheap. The fitting at the transmission is a banjo/hollow bolt arrangement. I would replace the seals on principle.
To make sure that this problem does not occur elsewhere, you can make some cushions for the clamps out of fuel hose.