hey look I understand what your saying, but how the **** does any of this help the OP get his truck running? can we quit the BS and help this gentleman get his truck to fire off, 70's and 80's american made V-8's werent exactly set to run on kill from the factory, none of the GM stuff had a 10 degree lock out on the vacum advance canister from the factory that I have ever seen or heard of, they were set up for nixon oil embargo era of 200hp if that, tops. so while others are giving him suggestions on how to get his truck back up and running as it was nearer a factory spec, making suggestions about different ways to do things that are far from factory does nothing but waste his time and ours.
I'm not saying your method is wrong per se, but as you said it doesnt work with a stock distributor, so you giving suggestions like you have accomplish very little in terms of helping getting his truck running.
I am done with the hyjacking of the OP's thread with this last reply to you, once he chimes back in we can continue to help him get his truck running