Looks like you need to come up with a way to hold the spool of wire
For my first little project I may just hang something off the ROPS..
Large pipe, small shank, and dry ground would be why you had issues getting depth.
That pipe needs to be a piece of 1/2 or 3/4 conduit to match the ripper and tooth size. The tooth size and angle just isnt enough to overcome the resistance of the pipe to pull it very far into the ground.
Tilting the thing by shortening the top link would help it dig in a little more at the front, but that will also raise the pipe/wire at the back, so I dont think that is gonna help much.