2001 5.3 in 99.starter cranks always

[dmartin1]

swapped in a 2001 5.3 and 4l60 into a 99 silverdo 1500 2wd.
wiring hrness from the 2001 with the engine.
compuer(ecu/brain whatever) is from an 03/04 suburban 2wd 5.3


it is nearly ready to try and fire, except as soon as i connect battery, the started begins to crank over, even with key off or out.
the starter wires were big and small(size specific) so i couldnt have the wrong one on the wrong post

i am attempting to find wiring diagrams( i already have the c1 and c2 pinout diagrams)


any idea whats going on?

[Nochance]

The little wire on the starter is the start wire it should only have power while the key is in the crank position. That wire is either shorted to battery power or the starter solenoid is shorted. I would check to make sure when you tightened the wires on the starter that they are not touching each other on the solenoid.