I interpreted "flicker" to mean that the idle is adjusted so close to the cut-out point for the ALT lamp that the lamp sorta bounces on-off as the idle fluctuates. That's how I've always set mine-- sometimes the idle is a tad high, sometime a tad low, it'll vary. It's not a computer-controlled fuel-injected engine with feedback loops to give 800.0 RPM all the time.
'73 R60/5 Toaster
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