Why won't Midnight Club Los Angeles: Complete Edition download on my PS3?

Okay so since there's a flash sale going right now, I bought Hitman HD Trilogy and MCLA for a very good price, I have an old model 80gb PS3 and I only have 10 gigs left of space, when I try to download MCLA, I get a message saying "There's not enough free space on the system storage" even though the game is like 5155 MB big and I have 10 gigs left, does that mean I have to erase some things? All day I've been erasing music from my PS3 since like in total the music is 50gb big (yeah I know I listen to a lot of music) and I at least erase like 20 gigs of music, I want to play this game already,
I was able to download and install all of the Hitman games that I bought and I have GTA SA, minecraft, and mortal kombat trilogy installed, is there a limit to how many games you can install or does this mean that I have to have more space so that MCLA can run smoothly?