safe way to connect 14ga to 10ga?

Thanks what size butt connector is that

A yellow one.

I just got a 8 ga amp kit since most places don't carry 10 ga unless online... And I'm going to solder so is this 40amp fuse too much or will I be fine

What size fuse is in the grey thing in the yellow wire of the radio.  There is no need for anything larger than that.

The fuse in the grey thing is the proper size for the wire on the radio.  The fuse you put at the battery needs to protect that wire.  Earlier I said there is no reason for it to be larger than the fuse in the grey box.  Let me rephrase that, It has to be the same size as that fuse to ensure protection of that small wire of the radio.

Ok well now I gotta find a 20 amp tube fuse

Hmmm...Might have to go online for those 20 amp fuses...Not sure if someone would stock those...? You could always replace the entire fuse holder...maybe to a mini ANL fuse holder($10-$25 most install shops should carry these)...? There are some automotive(blade) fuse holders($5 +) you could replace it with , but sometimes they have connection issues where leg of fuse slides into fuse holder(female spade)...But are as easy as going to an auto repair store to purchase and find replacement fuses...! Though i would recommend just sticking with the AGU Fuse Holder(at least) and ensure that that you get a good (snug) connection at each end of the fuse holder where the wire is inserted...! Also keep the fuse holder as close to the battery as possible...! Hope i helped some... Solder would be the recommended way to make the connection at the stereo...A good connection will be obvious after soldering and is usually the preferred method...Although most shops would probably just use a Butt Connector and usually holds up just as well with a quality connector and crimp...!  BTW Mr. Idiot...Where did you get the Connector Holder in the pic(probably could of came up with a better name...ehhh...)...?M.E.C.P & First-Class

Go slow and drink lots of water...Procrastinators' Unite...Tomorrow!

Tommy, that is the plug on the end of a Captain Morgan flourescent light fixture.

i am an idiot wrote: Tommy, that is the plug on the end of a Captain Morgan flourescent light fixture.

Enough said...!

M.E.C.P & First-Class

Go slow and drink lots of water...Procrastinators' Unite...Tomorrow!