Reen is pretty much spot on with his recommendation. I'll just add that converting to coil-over suspension gives you the ability to easily make tuning adjustments that you either cannot make or that would be rather time consuming with your current setup.
agreed and that mainly relates to corner weighting the car or adjusting shock bias, some small ride height adjustments can be made but limit that to 1/2-1" or less. any more than an inch and you'll move the shock to far from the center of it's travel.
That is correct. To move beyond the shocks preload adjustment range, the shock mounts have to be moved or changed. The g-Bar rear suspension's upper and lower shock mounts are both movable. The front coil-over shock tower mounts can be changed to a taller or shorter mount; or a one-inch extended top shock eye can be installed to raise ride height without affecting shock travel.