Ya know, i have done stuff before like this, and i always get super angry and frustrated, then i stop smoke a heater and remember what a buddy told me, go back to basics, KISS (keep it simple stupid).
It sucks you may have to tear it down again but start from the connectors and work your way back up to the bars.
I dont think anyone has a magic answer for you, i think you just have to honestly go back and recheck your work, because 90% of the time the response is a wire pulled lose on a plug etc.
On my sporty when i installed apes, i double checked my work and i still mixed up a wire, swapped the hi beam and the oil light plug so when the bike lost oil pressure on shut off the hi beam indicator came on, and vice versa.