Question regarding suspension upgrade for a 1966 Skylark

Hi, new here, first post, just curious on opinions using the pro touring stage IV kit for the 1964-1967 chevelle. This car has a BONE STOCK under carriage, and by that I mean manual drum brakes. I'm looking for an "all in one" kit to completely re-do the suspension and brakes. Things I'm concerned about:

I'm a garage mechanic, not a professional, with basic tools and jack stands. Is this something a mechanically inclined person can handle, or do I need to find a shop? I would like to do all the work myself over the winter.

How drastically would this kit change the stance of the car?

Most importantly, would this kit be pretty much bolt on? If it requires special welding and adding metal, I will need a shop.

If this kit is not right and you know of one that is, please by all means let me know! I Built this car myself, from the engine to the paint and everything between, but I'm not real savvy when it comes to suspensions.