If the aging memory still serves, your Leverage is a Diana 460 clone. Maybe try talking to Mike at Flying Dragon since I think the XS28M rifles he sells are basically the same thing??
The Leverage an XS46U are the same gun. If it's a clone of anything it's a TF99. Just about the same trigger. I don't think much can be done for it. Any trigger that's stamped out metal is not very sophisticated. Sale the leverage and buy a 97
I'm probably like a lot of guys, had one and not in the market for one. Best way to pull a bad heavy trigger with least effect on the gun is not pull it as much as squeeze it between the trigger finger and thumb with the thumb on top of the stock.
I bought mine in 2012, and every spring when it gets to be airgun season here I drag out, shoot it, then google to see if anything's changed with respect to a fix or replacement for that trigger. Status: not much beyond whatever benefit gained from clean/polish/lube.It's a shame because apparently they still make and sell them, they shoot as well as can be expected given the trigger, and people want to like them.
LOL... I wouldn't adjust it at all. I'd sell it like I did the last one I had. The gun is too heavy for my taste...