Yes you can use even a 500 amps alt on your car and will ve even healthier for the charging system. Some adviced mods are on the way just in case. No need to get a wire straight to the batt, that will bypass the amm. Please make a search about bulkhead bypass ( or parallel wiring ). Stock amm can be kept in place. Amm just read what batt sources or get charged, not the full alt ouput. Of course IS INCORRECT source anything from batt because amm will read it as a discharge and will add a load on it which is not needed. With amm on cars, every device on car must be on alt side.

An alt just source what is requested by the system, not its full output capacity. Bigger capacity alts will guarantee a nice output capacity at iddle ( the bigger problem on our charging systems )