Slide out not fully extending at bottom

I have the same problem with my Vizion, also a Keystone product. There are instructions online as to how to adjust the cables. The slide also sags slightly when extended. The top starts moving before the bottom when extending. My problem is I can't figure out if I am to tighten the bottom (out) and loosen the opposing or losen the top and tighten the opposing.

I suppose someday I will just take it in and have it done correctly.