If you don't have any luck locating the fuel resistant pieces you need there could be a few more options...If the metal 90 section is only a foot long you could fill the tubing{completely} with sand then make your tight bend...the sand will keep the tubing from collapsing in on itself...Then just use small sections of rubber for the vibration free splices...Another option would be to use the same procedure on the tubing and cut just the 90 out of the tubing and install it in the rubber hose essentially making your own preformed 90 in the center but leaving inches for the connections at each end...I use the sand method on aluminum A/C lines for custom routing and it works great !!! Just make sure you thoroughly clean the tubing out with compressed air and a garden hose or other means you have available.. ..