Sounds like you have some good plans.
I have a Pulley Boys puller here I will rent you for $10 plus the cost of shipping both ways -a Flat Rate Priority box will be big enough to hold everything I believe. They are somewhere around $9 one way. I have new M8 set screws so no need to replace as I will use the $10 towards a new set. I can get it shipped out tomorrow if you can paypal $19.
On the high performance cat simply go on ebay and find a Carsound (Magnaflow) 2.5" high flow cat, or better yet (and for lower price than the GM cat) get a Hogan Performance 3" DP with high flow cat for something like $200. It is a direct bolt-in if I recall correctly. I am not sure what there website is, but if you do a search here on BC for "Hogan" you will no doubt find the link fairly easily.