Not going to say this will help ya, but most often that I smell fuel on a gas Volvo, but see no appearent leak, it tends to be a bad fuel regulator. To check it, just unplug the vacuum line to it & check for fuel in the line or strong fuel smell. (I find it best to drive the car a mile or so prior to the test in situations where it's not immediately obvious)
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85 740 gl NA manual trans 87 740 gle NA zf trans 88 740 gle turbo wagon AW trans, loaded & fun.