Help with crossover capacitors


I am re-capping some Altec Lansing 890C Bolero speakers.  They have 6uf/50volt and 3uf/25 volt caps.  What will change if I use 5.6uf and 3.2 caps?  I can't find the exact 6uf and 3uf values.  Should I go a little bit higher on those values or lower?  Any suggestions?  I'm looking at Dayton, Mundorf or Jantzen caps but I'm open to suggestions.

dannybad
Great.  I think it will be fine as I really don't push them too much. Thanks for commenting.  Everyone on this thread has been so helpful.
And another question:  The resistors are 30ohm 15watt and 15ohm 10watt.  Mills makes both of these in 12 watt versions.  Will this work?
Two 15ohm 12watt resistor in series will give you a 30ohm 24watt.
I get that, but does that actually deliver more wattage to the speaker? Or does it give headroom to the circuit?
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The resistor power rating is the maximum amount of power that the resistor can withstand. It won't give your speaker more power, I believe the designer use a 15watt resistor for a reason.