problems starting truck

[69ChevySB]

my battery wouldnt hold a charge so i got a new one now when i try to start it my starter just turns my motor over but it wont fire up i tried it a few more times then saw something smoking under my hood...
i looked and it was one of the wires that goes into one of the harnesses plugging into the firewall
it was a wire with some kind of material around it which was all singed from when it was burnt. at the end of it had two yellow wires..one going to the starter and the other end going to the hei distributor could this be my problem??
maybe i had a bad connection and something caused it to burn up? if i go to the junkyard for a 69 pickup and unscrew that one bolt and unplug the left harness with maybe 1foot of each wire ...if i hook all these wires up how they were and replace the wire that burnt up, should my truck start up or does it sound like something else is wrong. help i want to get it going again thanks