[dana44]

Welcome to the forum. The distributor vacuum advance, if you stand in front of the engine and look towards the distributor, remains at about the 7 o'clock position. There actually should be many pictures of the engine on the web to look at as an example, probably the best way to get it right. If you haven't turned the engine over, the rotor has to point to a specific sparkplug order when installed, hopefully you know which one it is supposed to go to.

 

[valiant67]

If you are talking about the distributor cap going onto the distributor, it will only install one way. There are two notches that locate it and one is larger than the other.

 

[Bob Lincoln]

Yes, Mark is right - the cap only goes on one way. For slant-6, the firing order is 1-5-3-6-2-4.

Dieseling can be caused by advanced ignition timing, idle too fast, or mixture too rich. Make sure you check all of these. We can give details if necessary.