Need a new ignition box for nitrous

[Diabolic]

What is best option here? I will be putting it on my 93 Lightning with an intercooled S-Trim at 12-14#'s and a 150 in 1st gear. I want to be able to pull an additional 4º in 1st gear only and then get the 4º back as soon as the system is disarmed. I may run it 1st, 2nd, then off in 3rd. Digital 6 perhaps? Would that do the trick or would I need something else? I just bought this 6AL but then decided to run both poweradders.

[crashogden]

msd retard box should do the trick

[DriveWayBuilt]

Digital 6 with the nitrous on a window switch. I run the digital 6 and the timing change is instant.

[Diabolic]

I'm going to add on the MSD multistage retard box.