would 300 watt speakers be too strong for my battery/alternator?

300 watts of maximum peak system power
60 watts RMS system power

 

No...

Speakers can only draw as many amps as the amplifier can provide...

Jeff

 

so they should work?

 

They should be fine..

 

RMS is what your lookin at anyway... 60 Watts is fine for your system... Im putting a 1300 watt amp in, and I dont have any electrical problems. The factory deck wont give those speakers enough power, so check out an amp and a line output converter for that.