Hi,

Currently we do not have plans to add individual level leaderboards for GP mode, but we do have them for Time Trial mode. These leaderboards can be found at https://www.mariokart64.com/mksc/ . You're more than welcome to join our discord server if you'd like more info.

Luigi Raceway 3lap NTSC World Record is 1'38"17 (Not converted from PAL). You can view all the NTSC World Records here: https://www.mariokart64.com/mk64/wrn.cgi