engine break in questions

[fr3ed0m]

so i finaly got my truck running ive put about 10 miles on the motor in the last 3 days so far it seems good but here is my question, what rpms should i bring the motor up to the highest this motor has ever revved not counting the cam break in is 2k rpms problem is i have no exhaust i just have long tube headers so its pretty loud right now, im getting my exhaust done today when i wake up so once its on and quieter should i be pushing it harder or to higher rpms? im scared to push it on open headers because i cant hear if the motor where to start knocking or anything with the sound echoing off every curb and wall in town, this is my first time breaking in a new motor so any advice would be awesome its a 383 stroker with a very mild cam if that means anything but i would assume its the same for most motors