Rebuilt bbc 454 all new M H stock wirring, neutral safety switch hooked up and new. ground from battery neg cable hooked up to fender. frame to body ground strap hooked up, and pass valve cover to body ground strap hooked up. starter wires are correct and have been checked twice. I have power at the starter and have jumped the solenoid and had the motor turn over. But when i try by using the key nothing happens dash temp light and emergency brake light come on but nothing when I turn the key. Ive played with the ignition and have tested to see if there is power comming from the harness to the ignition and a test light indicates yes. I have even tried to jump the wires on the harness near the ignition and nothing happens. any help would be great guys thanks. 1971 heavy chevy 4spd

You probably need to use a test light or a DVOM, and check for power going to your neutral safety switch, and then make sure that the contacts in it are closing and sending power down to the "S" terminal on your starter. May even try by-passing neutral switch. Hook the ground side of your test light to the negative battery cable, and get someone inside to turn the ignition to start position, and try and check the purple wire going to your solenoid to see if you are getting power.

Make sure the bat neg cable goes directly to a good engine ground, ie, the terminal is clean and the mounting surface is clean with no paint or rust, then run the grounds from there to the body, etc. My Chevelle neg cable is on the front of the pass head on an alt mount bolt. Tacky but working. I have a separate ground from the bat to the body, and a ground strap from the firewall to the rear of the head.

Make sure there is no paint on the part of the block that you mounted the starter to....

Make sure both ends of both battery cables are clean and make good contact.

Check the start circuit as noted above. If all that works, and still not crank, I would pull the starter, reconnect to the bat and test, and then bench test it.

I have power at the starter and have jumped the solenoid and had the motor turn over

That pretty much proves that the cables and battery are OK.
Sounds like no power coming out of the Neutral Safety switch like BigBocks66SS suggested.
Make sure it has power to it AND power through it.

Thanks for the input fellas. But youll never gues what the problem was. I test light tested every point from ignition to neutral safety switch and was getting power. But from switch down to firewall and there was nothing. I took the wirring harness apart at the the fuse box and saw where the purple wire leading from the engine harness to the starter pluged into the firewall and where the dash harness purple wire met the engine harness at the fuse panel completing the circuit. Well they werent even plugging into each other. M H blanked up when they initially made the two harnesses. Each purple wire on each harnesses plugged into nothing, they were in seperate holes. Needless to say I had to pull and reset the dash harness purple into the next hole over and now it works. Initial start up of the 468 scheduled for this friday night. Things to get to be prepared 104 octane and beer!!!!!!! Nuf said. Thanks again..

Thanks for the input fellas. But youll never gues what the problem was. I test light tested every point from ignition to neutral safety switch and was getting power. But from switch down to firewall and there was nothing. I took the wirring harness apart at the the fuse box and saw where the purple wire leading from the engine harness to the starter pluged into the firewall and where the dash harness purple wire met the engine harness at the fuse panel completing the circuit. Well they werent even plugging into each other. M H blanked up when they initially made the two harnesses. Each purple wire on each harnesses plugged into nothing, they were in seperate holes. Needless to say I had to pull and reset the dash harness purple into the next hole over and now it works. Initial start up of the 468 scheduled for this friday night. Things to get to be prepared 104 octane and beer!!!!!!! Nuf said. Thanks again..

Glad you got it figured out! It's amazing how a little common sense troubleshooting can find the simplest problems.

Thats the truth. You try to ask as many people as you can. But in the end running the basics can most of the time solve the problems at hand. Im very happy and this has been along time comming. Ill up date how the start goes. Thanks again to all my chevelle brothers out there.

I had the exact same problem with my M&H harness. I really mad by the time I figured it out. It was a sunday so no customer service. Overall though It a really goo harness.

Well glad to know i wasnt the only one. But I gues if a restoration was and easy thing than everyone would be doing it.