beaterC10 your are correct 83 and 84 i have an 84 that i just had to rebuild the dist. the dist. also has two pig tails or wire harness coming ut of the metal part of the dist. i believe you can cut two wires and jump the to gether and then you can use that dist but without these wire connected to the esc or jumped across it will not fire this is really all i know about these b/c like you i thought all hei's are the same until i messed with mine
![Confused](http://67-72chevytrucks.com/vboard/images/smilies/confused.gif)
you can use the one you have but you will need a buddy that knows what wires to cross for sure and if thats not available than another dist. will be needed best luck and i hope i didnt confuse you due to me not knowing all about these types of dist.