This might be a dumb question but , will a V&H 2 to 1 Pro-Pipe off a 2012 Switchback fit my 2003 Road King....

 

Not without some modifications, it's not a straight bolt on and may not be worth the effort.

 

I found a pro-pipe (new) for dirt cheap , off a Switchback ,just wondering if it would bolt up to the heads without modification, I could change the brackets for the rest

 

Good question! Check the V&H website to see if you can find the mounting points. On a touring bike the muffler is hung from the saddlebag bracket, I'm not sure how the system is supported on a Switchback. The pipes will fit at the heads, its a matter of what happens down by the trans and the rear support. If you can see the system in the metal that may help. You may need some metalworking tools and skills to make it work, so if you don't have them keep on looking!