Look at my hitch set up please....

How would knowing the actual weights involved be used to determine the number of chain links and the hitch tilt needed to make the trailer, truck and spring bars level?

Is there some kind of formula involved?

I am one of the biggest believers in knowing the scale weights. However, having said that I would appreciate TomG2 providing some empirical data or formulas that express tilt and spring bar chain links as it directly relates to scale weights. There is a clear relationship between head tilt and chain links but I have never found a relationship between links, tilt and scale weights. In her picture, if the camera's angle is not causing some difficulties in understanding the hitch setup, the tilt is perhaps excessive provoking the need for more chain links than generally warranted and resulting in the spring bars being lowered too much. This can easily be adjusted by lessening the head tilt a small amount and reducing the chain links. The tension would be the same regardless but the spring bars would be higher and less subject to touching the ground and a little more parallel to the frame. Lastly, the OP needs to use the tongue jack to correctly tension the bars. Just because she is not strong enough to tension the bars without the tongue jack is not justification for an improper spring bar tensioned hitch.

Again, a pic of the trailer and truck hitched on level ground would really help. If the trailer is not level or nearly so, all parameters need to be reassessed.