Opinion american autowire fuse selection for main dash feed

[stubbygda]

I am in process of putting a new wiring harness from american autowire into my 68 charger. I am concerned with the fuse that protects the main dash power feed. They use double mega fuse both at 175 amps. So i get the 175 amp fuse for the alternator/battery connection but looks like the 175amp fuse on main dash 10awg feed is way too much. i am no expert but seems the wire will burn up before fuse fails? I have seen some discussion of this on a couple chevy forums and the question was posed to american autowire but not resolved. I know there are some very knowledgable people on the forum so lookin for opinions or clarifications. i was guessing it should be round 50 amps not 175. Here is a schematic of the diagram they provide.

i am also using 4awg wire instead of 6 because i will be using a higher output alternator for dual fans, ac, electric fuel pump additions. Connections will be done at junction post versus the battery terminal on starter. Any help appreciated.

 

[Don Frelier]

Yes the fuse is way too big for a #10 wire.

Where are the new loads being fed from?

You are going to move the busbar correct?

 

[stubbygda]

fans and fuel pump from the battery, the a/c from the dash. i measured the ac blower at about 11 amps on high, compressor is sanden they say it is about 5-7 amps so i figure total for ac out of dash about 20 amps.
these guys at autowire are a lot smarter than i am any idea why they might design it with such a large fuse??
yea until i get my engine in not sure which side i will feed the alternator and thus the position of the busbar. the way it is now gives me a bit more length to the junction post and allows dash feed to come out on side closer to bulkhead but i can easily do it other way if works out better.