So according to this, the Bears were considering their options for moving their home venue from Wrigley Field. They ran a test game at (then) Dysche Stadium in 1970, but a petition by Evanston residents forced the Bears to look elsewhere.
What would then be the plausibility of a permanent move to Ryan Field be?
This is part-plausibility, part-logistical, and part-practical in terms of the question. So, feel free to be flexible here.