Has the system been operating normally before the module change? It sounds like you've got a dead short somewhere, or maybe an incorrect wiring connection. It's not unusual for a HEI system to draw lots of primary current, but a 20 amp fuse should carry the load OK. I'm not familiar with that system- - - - -which distributor and module does it use as the basic unit?
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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