I had the same problem with my pro comp 4", just recently replaced the front lift springs with a custom rear pack, the pro comps aren't arched different as far as left and right sides like stock springs.
Just put those springs on a buddy of mine's truck but welded on the 3/8" spring pad spacer that marlin has, leveled them right out.
![My Two Cents :twocents:](https://board.marlincrawler.com/Smileys/marlin/twocents.gif)