Line lock or leave as is?

I was just running my street BFGs so I just tried to back into the tracks coming out of the water box rather than roll all the way into it. You are probably right though. I just eased into the throttle rather than nailing it for the burnout. It did make a couple of revolutions before the roll forward. Maybe the combo of more throttle plus the line lock will hold it in the spin a bit longer.

I actually don't know what the laws here in AR are about line lock activating the brake lights but I for sure will be in touch if I find out that I need it to. It might not be a bad idea even if not required, especially after the 5 speed swap.

As soon as the tires are spinning it will require LESS throttle to keep them spinning. That doesn't mean you have to back out of the throttle. As the tires heat up, they'll drag the rpm down some.

Point of note;FWI
My 235 crappy front BFGs, with the line-loc on, Easily hold my Barracuda with either rear tires I run; The BFG 295/50-15 radial T/As, or the BFG 325/50-15 Drag Radials. And I don't actually have to shock the 295s . I just modulate the clutch and throttle until the tires slip.I have never actually looked at the tach as I do this, but I estimate the 295s will slip on concrete at about 1800 or so in first gear, Maybe less. The 10.97 starter gear really helps.