I don't have any experience with the Petronix kit but I'm sure if you visit their web page you'll find detailed install guides.
As for the advance springs, you're gooing to have to experiment with a timing gun and see how fast a curve you've got, it should be all in by about 3000rpm at the most, but not much earlier than 2600rpm ideally. Any slower or quicker than that and you'll have to obtain a selection of springs and try them to see what changes they make, that's where the kits like the FBO come in handy, a lot of the trial and error work has been done for you.
Set the timing using Daves procedure outlined in the sticky at the top of this section, it's a very comprehensive guide and easy to follow. Using the timing figures he outlines will perk the motor up nicely, give you a clean exhaust and plugs and even keep the motor cool