for coustom maps you need menyoo to ymap to convet the orignal
you dont need both just one of the files you also need portals to enter the interior 

for coustom maps version it gos to mods- update- x64- dlcpacks- dlc.rpf- x64- levels- gta5 -_citye- maps- custom_maps


for menyoo go to Grand Theft Auto V-menyooStuff-Spooner

once you install portals the folder Portals goes in gta 5 main dirctory

once you done you will need garagemoz1.xml to enter thru with cars
I recommend using the coustom maps version then load the garagemoz1.xml when in game and it goes in spooner folder