To start, I have a 69 pipe and the parts below.  

Does anyone have a pic of a 69 DT1 exhaust exit/silencer as installed from Yamaha?  The docs are not so good for this.  I ordered a few parts online and it makes no sense how they might be assembled.  Guessing, parts are wrong. I thought the stinger would slide in maybe weld to exit?? Nope.   I have to get the exhaust back to 100% stock before I finish tuning this thing. 

I have a 69 DT1 pipe. Ordered the following. If I could see what it is supposed to look like, maybe I could fab up something.

i.ebayimg.com/images/g/GPYAAeSw1LlqjOYQ/s-l1600.jpg
i.ebayimg.com/images/g/CXcAAOSwXrBnoOxW/s-l1600.jpg
 

The exhaust pipe and baffles changed within the 69 model year at approximately # 22,200 .
Your silencer is from a 68 or early 69 pipe .
The outlet is for the later pipe .
The later silencer ( baffle ) was  214 - 14753 - 01
They do come up NOS occasionally , but were also fitted to AT & CT 1 / 2 / 3 .
I do have a pic , but it's too big to load here .

is this the one you are referencing?  bike is dt1S first few hundred built serial 90,xxx
cdn11.bigcommerce.com/s-v5z9i/images/ste...7.1671133764.JPG?c=2

I'm thinking about joining the 2 parts above, just tack weld it as a test.    

 

That's the beast . It slips inside your exhaust , and has a hole to line up with screw hole in the pipe .
The outlet then slips inside the silencer ,stinger end first , and twists into place . The outlet has a threaded hole ,
which lines up with the other two , and a 6mm screw and spring washer holds it all together .
The DT1 S is a sort of 69 1/2 bike , so this is exactly what you need .
When you have all the pieces together , it will be make sense .