It turns out that it was the starter - I had it replaced today. It's good to have friends in the mechanic-ing business.

'98 Rodeo, Ranchos, OME 912s, General Grabber AT2 265/70/16s on steelies, Superwinch hubs, G80 code, Pioneer HU... two car seats and cracker crumbs.
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Illegitimus non carborundum.
Educatio est omnium efficacissima forma rebellionis.