starter relay is a blue relay by the passenger fender closer to the bumper. it looks like 2 seperate relays back to back/stuck together.
test that relay. or just replace its 18$ at autozone.
oh and i would also just make sure your motor is grounded. 90% of starter problems on swaps is bad or no ground. take jumper cables and put on negative battery terminal and then ground the motor with the other end and try and start.
Follow the + battery cable should connect to the starter relay (solenoid)
Usually when this happens the starter solenoid has failed -- remove the starter and have it checked/rebuilt. Some auto parts stores can run a check for you also.
have you checked the relay on the starter? and check the wire that runs from the started relay to the starter.
You didn't mention if you checked/tested the low beam headlamps or not.
Check ignition relay. Jump the battery directly to the starter and see if the starter is any good.
Is this an automatic or manual transmission?
Check the fuses and the starter relay.
If it is the starter that is grinding, the bushings are worn and the starter is "dragging" and not spinning fast enough to get the engine started. Replace the starter, chances are that the armature is damaged due to the dragging (grinding against the inside wall of the starter.
if you took the wires off at the battery to change the starter, make sure you put them all back on
cables and or check for good ground first.
Have you checked your fuses?
yes i can answer what is shorting the chevey tahoe fuses theres a promblem with the starter wires moving and touch and grounding on to the starter remove starter and adjust wirers