you can possibly get rid of the cruise [light throttle/high vacuum] bucking by using a 3/32" allen key into the advance can, and turning the can spring to a tad less vacuum advance at your cruise rpm.
e-booger did an article for mopar muscle magazine on tuning the vacuum advance a while ago.
look it up on their site. it's a well written piece, and should be tried before saying the heck with it, and just capping off the advance can.
in some instances, it makes a world of difference on the performance of a vehicle no matter what engine you have under the hood.
it has worked for me many, MANY times, while most just cap the can without even trying to tune it.
i highly recommend reading that article and applying it to your combination !