i just replaced the starter on my 01 silverado and i also replaced the clutch safety switch and now when i reconnect the battery the truck is trying to start

 

here are some possibilities:
-you hooked something up wrong when you installed the starter or clutch switch
-the starter is faulty
-the ignition switch is supplying power to the starter solenoid when the key its in the off position
- the clutch safety switch isn't working right, there should not be power going through the switch...the switch should be open unless the clutch is depressed.

I would disconnect the starter solenoid wire at the starter, connect your battery. if it doesn't crank by itself, that wire is shorted to power or you have a bad ignition switch.