Just see what parts were used to lower it and swap them out with stock parts. There are people all over with lifted and lowered rigs that would give away or cheaply sell their stock parts. I see 'em all the time on Marketplace. Or, tell us where you're at and maybe there's a forum member nearby that wants to lower theirs and would trade you their stock parts for your lowered parts.
Maybe post an ad on Marketplace to see if someone would swap you and do the work or help you as part of the labor to earn their "free" drop kit. Might make a new GMT900 friend out of it.