Been there done that. There is no shorter bar or cable. I didn't need to sneak between trees either. There's more to shorten that just the main tube and the left marker cable. There's also the fertilizer bar and that steel hydraulic tube inside.

I narrowed the wheel frame and moved the row units closer, had to drill a new hole in the hex main shaft to move the driven sprocket to the new wheel location.

The markers are shorter, but they can't be shortened enough to be at the tractor middle, but hit the far tractor front wheel track which on my tractor is a much more precise spot to see and my guess rows are not detectable. That's the way the factory narrow planter works too.

I had to replace that steel tube for the marker, mice nests rotted a hole in it. There were none available from the factory and 4 years ago, only 2 in dealer parts in the whole US. I coated the new one with Black Jack roof tar to slow the rotting in the future. I recall it was a pain to get that steel tube in place.

I used the plow coulters and ammonia knives to put down 32% 2-1/2" from the row and to cut straw so the trash whippers could separate it nicely. Fully no till.

Gerald J.