Man, I hate stepping into threads this late; the answer to the question that the topic poster gets is always somewhat messed up before I can give a decent explanation.

So, just to clarify:

1. You can't connect to a 1.5 PSP over WiFi to change files inside UNLESS you already have a USB cable. You can, however, using a USB cable, install an FTP program onto your 1.5 PSP to do just that. You must have a cable to do that in the first place, though.

2. There is no way around the 2.0 forced upgrade for GTA at thie moment. Hang in there, though! MPH and SXT are working on firmware emulators that will allow you to boot a 2.0+ firmware off a Memory Stick on 1.5, allowing you to (in theory) play 2.x games on a 1.5.

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