Is it possible to do this without replacing the PCB with a 360 pad?
Yes, it is possible.
You don’t have to replace the existing PCB. You can add a pad hacked 360 PCB and a switch.
As long as your PCB is common ground, and you have a Xbox 360 version stick, YES.
A Xbox 360 Pad hack is more for custom builds from starch or dual-modding a non-xbox 360 controller like PS3 controller.
It is rare to need a Xbox 360 PCB for a existing Xbox 360 stick right off the bat, usually its for sticks with a dead PCB.
The V3 SA is the PS3 version. Real Arcade Pro V3 SA: Amazon.ca: Computer and Video Games
I like the black box better. Besides I need a dual modded stick anyway.
Can you link me to a tutorial about how to add a switch and padhacking a 360 controller?
Opps My bad, I forgot
its easy enough to do
just take your dpdt/imp switch
and take your D+ and D- lines and hook them up to the switch
Only other time a complete PCB replacement is necessary is if your installing a all-in-one PCB like thePS360 or the Paewang Revolution
http://shoryuken.com/f177/intro-rules-tutorials-info-read-before-posting-209057/
Somewhere in that sticky thread there is a tutorial relevant to your needs.