Best place for line loc switch?

I am not understanding what you two are talking about. Why would you need a line lock off the line? The car is not going any where untill you let off of the clutch. So you don't need it there.

I don't under stand what you mean by preloading ether. Lets say you lanch at 3000 RPM. You realy don't want to have the clutch out much as it will be tuching making a bunch of friction that is putting heat in to your clutch and you don't want that eather.

not sure about the preloading thing either...in regards to the launch, you probably dont "need" a line lock, but it is definatly good to have...its good to have the security that the car will not roll forwards or backwards at all, even if the track surface is flat....i dont think i understand what you are saying- you are in first gear bringing up the rpms, yet somehow without having your foot on the brake as well you are not moving?