I've been running the 8477 problem free for about 10 years now. It's the one I'd recommend.
The 8350 should give the same service. Sorry to hear about your troubles. I've had similar frustrations that could've ended with gun fire.
If you haven't done it already, eliminate as many variables as you can from the msd system.
Temporarily wire it up with just the distributor and the coil(see page 7 of the msd instructions). No ignition box or tach. Make sure you have a good ground and if yours came with the rev limiter function make sure that wire is capped off. This could also be done on the work bench. Carefully that is. You'd need: battery, plug and coil wire, spark plug, and enough jumper wires to hook up the power and grounds.
Hope that helps...........J
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