nice thanks eckart hmmm..... is that on a single rear or dual?? the next mission is the brake porportioning valve. i could just use a wilwood valve so i can adjust it but im wondering about brake master compatibility. i know when i put disks on the back of my 85 toyota and my landcrusier i had i needed a diffenrt master. does anybody know what the differnce mechanically the masters are?? does that van have hydralic brake boost or vaccume? is there a parking brake in thoose discs? like whats on the superduty? im pretty sure the abs system is the same its just a hall effect sensor on the rotor with the pick up on the axle.