You would need the following (assuming four channels -- 2x KITS):
1.) 2x transformers 220VA-330VA with dual secondaries producing between 18VAC and 25VAC
2.) 2x Power cords
3.) Chassis with Ground (if w/kids) or "whatever" if not
4.) Hookup wire
5.) Speaker wire (if you don't have any)
6.) RCA phono connectors
7.) Solder "barrier-strip" or phenolic terminal pad ( AC mains to trafo)
8.) AL Heat sinks w/ heat sink grease. (a perforated AL 'slab' serves)
These are prebuilt and tested -- you have no soldering to do on the boards -- just hookup.
Or you could break down and get one of these --
UPA-500\\Charles