i bet the third mounting bolt is behind there...

i can see the bottom & back of the alternator from under the truck too, so if you haven't tried that direction...(i have a different motor than you but same alt location i believe)

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1999 xlt 2.5l 5-speed Supercab 159k
83 diesel 2.2l na
06 F250 6.0l psd
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