The clutch master is wilwood. Fits perfectly so far. I haven't decided on a roxor brake master with booster or just going with the master I currently have, which I probably will do at first. If I'm not happy with that, I'll probably go with the roxor cylinder and booster. The roxor brake master brake booster is I believe 7" in diameter and thinner than I've seen any others. Looks to be about 2-3" thick. Roxors have drum rears and disc fronts so the cylinder is matched to that. Should provide enough clearance. I have a v8 and looks like it would fit fine.