No spark, I'm lost

[6768chevylover]

Have an msd coil, pro billet dist., msd 6al box, street fire wires and autolite spark plugs. I had it running one day and it died on me in the drive way. Ended up being msd box went bad. Bought a new one and still won't start. Checked coil and plug wires and they are with in specs. Swapped out the mag pickup in dist. and is with in specs.. I still have no spark through the wires. I have power through the coil by nothing after that. Any ideas cause I'm lost? Its a 350 and I have grounds from engine to frame and battery. Thanks for any help