the front chassis brace uses 13mm head, dont know what the thread is, the bolt is about 20mm long ... mount them upside down so that the nut is engine bay side up
jack the car up for access to the wheel well
use a 13mm spanner in the wheel well and a socket kit on the top to do them up

the 4pnt rear bar should have come with some plain phillip head metal screws
check the hole size on the brace and grab some screws to match
i just got a corded drill with a phillip fitting and went to town on it

if you have any more questions dont hesitate to ask =D