I have my aftermarket dash (6 autometer guages) running into my IGN/hot on the fuse box, the IGN wire for my stereo, AND I just re-hooked up my amp which also called for an IGN/HOT slot. Problem... I only have one and im blowing 20a fuses. I dont know how else to hook this stuff up without another IGN/HOT. Larger fuse, 25a or 30a?? It worked before, not sure why it doest now.

Be careful dont just put larger fuses in especially if your wires and box are getting hot. You may become a boy scout and start a fire. What you should do is use solenoids and switch your amp and stereo power using an ign. and a designated hot wire from the battery, or a Pos. Post. Even though there are connection posts near the fuses you should engineer your own harness using those posts as the switching power for a solenoid.

This is where you want a seperate fuse panel with a dedicated feed wire and powered up via relay controlled by the main fuse panel IGN terminal.

I am not surprised that the stereo and amp together blow a 20A fuse. The original wiring only supported a 10A circuit for the radio in '68, and I doubt that '71 was much different. One of the changes I made when I did my dash harness overhaul was to replace the radio feed wire with a larger size and up the circuit to 20A.

You should be able to run the Autometer dash off of the original wiring and fuse panel without problem. It is just the stereo and amp that really need to be on their own at this point. I would look for a product something like the Painless CirKit Boss #70113 3-circuit auxiliary fuse block with 40A relay.

Im not running an amp anymore, just a stereo. I dont really want to add another fuse box because somewhere down the line I am going to replace the entire harness with a painless kit, engine and dash side. Im sick of this stuff, the chops Ive made plus the past owners over the years... no fun. So for the time being I can add a seperate fused line or something with a switch?

I was thinking of taking one of these things and putting it on its own power line with a switch, my battery is in the trunk though ... so thats another wire all the way down though! Yeah it sucks, originally it was only a 10a fuse, not much at all. I was going to try my luck with a 25 or 30, if that doesnt work put on a new line of some type, and as said before... I cant wait to rewire it with all new painless stuff.

I was thinking of taking one of these things and putting it on its own power line with a switch, my battery is in the trunk though ... so thats another wire all the way down though! Yeah it sucks, originally it was only a 10a fuse, not much at all. I was going to try my luck with a 25 or 30, if that doesnt work put on a new line of some type, and as said before... I cant wait to rewire it with all new painless stuff.

No need to go all the way to the battery.
Connect a fusible link to the positive battery cable up front for power feed.

Positive battery cable up front, like around the alternator or starter? Any specific size for a fuseable link? Thanks :)

Positive battery cable connection at the starter solenoid.
Fuse size depends on wires size, wire size depends on load.

If I went that route, wouldnt it act as an always HOT wire? If thats the only way I could just get a toggle switch and put my guages all on that line, I wouldnt mind that. I put a 30a fuse in there for now, it seems fine... so far.

It's pretty easy to add a relay if you don't want it to be "always" hot.
A relay could be connected to be energized when the key is turned on (conected to "ACC" terminal) or could be operated by a togle switch.

I was thinking of taking one of these things and putting it on its own power line with a switch, my battery is in the trunk though ... so thats another wire all the way down though! Yeah it sucks, originally it was only a 10a fuse, not much at all. I was going to try my luck with a 25 or 30, if that doesnt work put on a new line of some type, and as said before... I cant wait to rewire it with all new painless stuff.


You dont have to go all the way to the trunk. You have the wire still connected to the starter and the alternator. You could take leads from either point.

IMO I would put a solenoid/relay and power it using the original stereo feed as it uses Milliamps to turn on. You then feed it with a larger line 12GA maybe and a 30A fuse before the solenoid.You want to place the solenoid as close to your large power source so that you have less "hot" wire running through your vehicle.