Great descriptions for "front" and "back" of cartridges - provides clear references points. Thanks!
However, based on those descriptions, it seems the supplied paper contradicts that a bit.
My cartridges came to me with the oblong colored plugs at the front. On the paper, all references to these type of plugs call these the "air vent".
Similarly, on the cartridges I received, the plugs at the rear were the clear round ones. The paper refers to these plugs as covering the "refill hole".
Based on your initial reply, I have removed the clear round plugs at the rear of the cartridge - but I'd really appreciate your confirmation that this is right.
In my NEXT post, I'll try to attach an image file of the paper I received (I had to crop it because of your file size limitation). If you look at this, you might understand my confusion.
I hope I may ask you to please reply again. I just want to be sure I've set this up right, have the right holes unplugged, and know where I must refill when the time comes.
Thank you very much!