normally you can shift a song by simple ratios that are in the original key (like how a perfect fifth is considered a 3:2)
Taking that example, we'd adjust the bpm to around 82 (123*(2/3)) and the arp would stay pretty nicely within the key aside from a few notes here and there. That's what I did with the bass in the original track. I stretched it by a 2:3 ratio to take it down a few steps. Did I explain that clear enough?
what the fuck this bops
any track that's open for remix, feel free to remix! By the way, the arp is out of key now that the samples have been stretched