Straight Pipes

Subscribed. Are you going to post pictures and videos when finished?
The H pipe is part of wave tuning. Since you are running (I assume) a 3" to 2.5" header reducer your wave is different and possibly moot compared to running 3" diameter collector extension. I dont know much but I suggest that the location is dependent on your engine torque band. To optimize the location, length and diameter of the balance tube (and subsequently your engine torque), you should talk to an exhaust tuning guru or research exhaust wave tuning. My 2c.