Take serp belt off and on some models you will need to take air cleaner hose off and any other parts that are in the way ...be sure to disconnect battery before messing with wiring ..
The alternator can be a pain to get at with some of the bolts and even on some the doghouse will need to be removed for access.....doghouse is the housing in the middle under the dash on vans ..........but if they made them easy everyone would want to work on them I was once told ....
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Try fixfault.com to fix vans.