rejracer

look at the 79-83 zx distributors. they look almost identical to the stock unit except the ignition module which is on the distributor, but that too can be relocated to somewhere else on the vehicle for a more stock look. I would not bother though. Then you also must put a resistor inline with the stock tack to get a consistant signal. I am running that setup now on my 240z, and have been very pleased with it for the last 12 or so years it's been on the car. It's nice as it does not get out of time, and never needs the points adjusted.

I would fix it. Unpredictable timing can damage your engine. It can interfere with the normal operation of the breaker plate which can cause too much timing at WOT.

Check the basics first. Make sure you are getting fuel, that your primary wires are still connected to the coil/distributor. Check for spark by pulling the coil wire from the coil and having someone crank it whist you check for spark.. I had a similar failure years ago and it turned out to be an alternator that shorted out internally which caused the fusible link to burn. I also had intermittent problems with it suddenly dieing on me and it was some wires that had broken internally that powered the coil/dist, it was a quick fix.

LT1's from different chassis had different length dampner hubs and diameter dampners. IIRC an LT1 from an Fbody(camaro/firebird) has a 16mm shorter hub and a smaller diameter dampner than an LT1 from a Bbody(caprice/impala/roadmaster). I am not certain what the Ybodys(vettes) have. Iron headed Lt1's came from the b bodys. Aluminum headed LT1's were in the F and Y bodies. Ybodies had 4 bolt mains. If you need to space it out a dampner you can get the B body hub. Then just space out the accessory bracket with spacers from Karl Ellwein. http://www.ellweinengines.com/ in re-reading your post you noted that the dampner is 7.5" which is the same on my 94 impala. If you do have the F body setup then a set of spacers and some longer bolts could buy you another 16MM backward. some interesting reading from the B body community concerning hub lengths: http://impalassforum.com/noncgi/ultimatebb.php?ubb=get_topic;f=1;t=011166#000000 http://impalassforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=004536#000006 http://www.impalassforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=004367 edit: http://impalassforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=18;t=001345 pay attention as there are a couple of different setups referenced above. some may be more applicable for your goals than others. Hope that helps.