Check your fuses. There is a separate one for the fuel pump on my Stryker. It possible you dead shorted something while wiring your leds etc.
This is long and boring but be patient and start from the battery(like others said make sure connections are tight) and then work your way to the starter etc. If you have the service manual all the better.
Be METHODICAL. Don't rule out anything. Remember the owners manual where they ask you if it is plugged in? Silly stuff happens. Case in point: The new battery. new yes. proven no. Take a reading and make sure within specs. Replacement batteries can have bad cells. Odd but it does happen.
Finally, and sadly, from my days in IT we had a saying LIFB (Last Installed First Blamed). Rude, yes, true almost always. Your additions shouldn't have caused this but you may have blown a fuse, inadvertently cut a wire(or wrong wire), jogged something lose etc.
Take your time, fix it, post it and then have a beer and laugh with the rest of us when you find it if it is your fault
In the end all that matters is to get back on the road. 4+ months for me due to weather here in Chicago