Any time! Since you have a spring and fuel pin it won't hurt to do it now. A 1/8 inch bump will lower EGTs and give a little more hp. It will lower boost, so don't be alarmed when it goes down some.
pete
Just enough power to break everything behind the crankshaft.
Shouldn't hurt anything. Timing is something you need to play with until you find where YOU like it. Some people like more top end (more timing) some people would rather have more low end power (less timing).