Dferney20

When I turn my key on I have power all the lights and gauges work fine and I go to start the truck and it loses all power as soon as I stop trying to start it the truck regains all power like normal. I replaced the solenoid on the firewall and had the starter tested and it tested out fine. Ilove also replaced the battery and the connectors. I am guessing its shorting out somewhere? I made the mistake of not marking the wires an how they hook back up but after doing my research I am sure they are hooked right anybody have answers ?