New Engine won't turn over!! Help

OK I rebuilt the 340 "BY THE BOOK":read2: its ready to start for the very first time....but It turns over so hard kills battery in one turn... Should I or can I do something to help? I've never done this before so I'm a total rookie.Is there something I'm forgeting or is there something I should do first.
Need help here please....
NEW ISSUE!!!! cylinders are full of gas!!!I pull all plugs and there it is. thats why she won't turn ...full cylinders.. so now what do I do?? whats up with that? Yes I have an electric gas pump. Eldebrock carb.

my cell 307-217-0242