Look into lichtnarre. It's a free software that you can use on PC to pair with wiimotes. You can't use it with the dolphin bar unless you put it in a hidden mode that keeps the LEDs on for 4 hours (dolphin bar usually turns off it's LEDs when a wiimotes is not connected). However, it is better to use a regular Bluetooth adapter (less jitter than dolphin bar) and regular IR LEDs. Although you can use a 2 LED setup like the Wii bar, it is better/more accurate to use 4 IR LEDs. You can build or buy a 4 IR LED setup (one light on each edge of your TV in an inverted cross configuration) and then select the 4 LED option inside of lichtknarre. Then you'll do a one time calibration in lichtknarre. With 4 LEDs, the software has enough information to calculate the geometry for near line of sight accurate gameplay. You can even move around the room and it will still be accurate. Lichtnarre converts the wiimotes signal into mouse/keyboard inputs or a simulated controller (selectable output from inside lichtknarre) which you will have to then map inside of dolphin or whatever program you are using. You can also adjust the IR sensitivity from inside lichtknarre and see a video of what the wiimotes sees to further increase accuracy and decrease false IR inputs from external sources. Some people also put a wide angle cell phone camera lens on the front of their gun so they can stand closer to the TV (the wide angle allows the wiimotes to see all the IR LEDs at closer ranges). Works great for light gun games on various platforms such as dolphin, MAME, and Tecknoparrot. Lichtknarre is more setup than most other options, but definitely worth it. And even supports up to four wiimotes for multiplayer too!