To make marinade:In jar, combine V-8 juice, salad oil, vinegar, and
salad dressing mix; shake well.In bowl, combine vegetables; Pour
marinade over all. Marinate in refrigerator for at least 4 hours,
stirring occasionally.*
NOTE: If not going to be eaten the same day, perhaps wait to add
mushrooms and cucumbers until a few hours before serving they
will go limp instead of remaining crisp. The balance can be combined
and marinated up to a couple of days ahead of serving in the
refrigerator.
* I have found it works best if you marinate in a tightly covered
bowl. Then when you are in the kitchen and think about it, you can
just turn it upside down, shake it a bit, and put it back in the frig
instead of stirring it.