the cylinders that are angled are usually for the fronts so when turning it gives more clearance for the lines (hoses). as for the interchangability of cylinders, as long as you can find the correct spacing on mounting bolts, the only real difference in the cylinders is the diameter/size of the pistons. larger will obviously need more pressure to activate and a heavier spring to return them. suprisingly orielly auto parts has a decent stock of in house cylinders that you can compare to yours in hand for better reference. buy it from somewhere else though. -DVZ
