off the top of my head (trying to remember) there will be two exhaust port clamps, 4 pipe clamps, 2 can brackets on the 2 into 2 system so 10,11,12,13,14 mm sockets long extension, short extension, ratched socket handle, possibly a 12,13,14 17, ring spanner and some sort of bar to hold up the headers while fixing the exhaust port clamps. that is assuming the clamps are STD bolt type if the clamps are allen headed of course you will need the matching driver.
fit the headers first get into position square on the ports and gaskets do up the nuts, manouver the pipe extenders (after fitting the clips line everything up. add cans/brackets to the rear peg mounts make sure all is square and bolt everything up tight.
note, with the rad in place the exhaust port header bolts/nuts can be a PITA to locate and keep square that is why a long extension is easier, good luck.