I need some help

[cam427]

i'm probably not posting this in the right section but i need some help.
i bought a 1981 c10 with a 350(5.7l) the other day,i drove it home turned it off and on multiple times. i was going to start the truck this morning and i turned the key to the run position and the stereo turned on so i knew i had power but when i pushed the key to start it i lost power.i thought the battery was dead so i got a known good battery and hooked it up,i turned on the lights to make sure i had power and they worked. turned the key and still no power to the cab of the truck and it wouldn't start. the person that sold it to me said it had an ignition problem and that he had a new ignition switch(the actual electrical switch) but he hadn't put it in yet so i got it from him and put it in my self. got in the truck turned the key and again, no power to the stereo or anything that needs the key to be turned on to work. i checked the fuses but i don't think any of them were bad (there might be some main fuse that i dont know of). I have been told to check the starter and starter solenoid for power when the key is turned to start,when i did there was none but does that have anything to do with me not having switched/accessory power or is it the cause of not having power. if anyone has any idea what is going on your help will be greatly appreciated. also it has a tilt steering wheel with the gear selector for the automatic transmission on the steering column if that information helps.

[gchemist]

Welcome to the site. You have a blown fusible link. Check the power junction open link next to the windshield wiper motor. Follow all those big red wires. One of them is blown. You should be able to feel it. Just pinch the wire. If you find a soft spot, you found the broken link. Cut it and replace it with another link. You can buy short fusible links at the parts stores.