Help with initial start up

[19Suburban69]

I’m installing 6.0 w/4L80 in my ‘69 C20 suburban. First time playing with LS. I’ve got most mechanicals done and it’s down to wiring and exhaust. I need to know if I can do initial start up with open headers. I’ll install O2 bungs in collectors and plug in sensors. If not I’ll have to trailer it 40 miles to and from exhaust shop, then go thru start up. I’m wiring challenged so I’m at a point I need to find someone to come over to guide me. I’ve got more questions, but I’ll stick with exhaust issue first.