YOUNG GUN: Putting Nitrous on 318!!!

Well I drove the car last night with the nitrous hooked up. I ran the 100 hp jets. I backed the base timing down to 10*. The car seemed to run pretty good. I think I could advance the timing a little more, I also think it could handle the 150 shot as well put i dont wanna get too greedy yet. I was wondering how I can advance the base timing without advancing the total timing. Don't the two go hand in hand? If the base timing increases doesnt the total timing increase as well? Also my kickdown linkage wont clear my air cleaner base because i had to put a drop base on to allow it to clear the hood. Any ideas for modifying the kickdown?, Right now i just have it strapped all the way back so I have full line pressure all the time and I'm shifting it manually.