I found 2 mysterious peices in my Blazer that im hoping someone can enlighten me on. 1) When I was doin heater core change out, I see a box that looks like an ECU mounted under the dash way up high. My truck is 84 with carb. I have also yank factory carb and distributor (put HOlley 650 and mallory dist) 2) Under the bottom of the dash right beside the ashtray towards pass. side, there is a Black Plastic outlet looking thingy that protudes down some. It looks like a cig lighter outlet, but when I tried to plug anything in with a cig light plug, it wont fit the lil outlet is smaller than conventional 12v cig plug. It also looks factory. Sorry dont have any pics. Can get pics if necessary though. lol Anyways, any insight is appreciated.