john of or

I've been having a problem with my 2004 SR5 4 Runner not starting (105,000 miles). I've done a lot of research concerning the problem but I've not been able to find what the problem is as of yet. So far I've : Replaced the battery, checked all wiring (visually and with a DMM for cont.), checked the PNP switch (position only and for power to the switch), replaced the starter switch, checked the starter solenoid (V-8 engine) and the starter relay. And still can't find out what the problem is. It will start if I'm persistent in the morning. After the initial start in the AM it will start throughout the day. Does anyone have any other ideas? Much appreciated!