Just came across this. (Work has been busy lately so if this was posted before forgive me). Bears can clear up to $72mil in cap space with simple restructures of contracts. Maximum restructuring could generate up to $147mil although I'd imagine that brings plenty of pain in future years. Poles has quite a bit of flexibility to improve this roster, more than I expected.
https://overthecap.com/restructure
"A simple restructure converts payments into prorated signing bonuses within the confines of the remainder of the contract. Teams typically have the ability to unilaterally execute simple restructures without any action necessary from the player."
"A maximum restructure increases the amount of cap space via conversion into prorated signing bonuses by either extending the contract or by adding void years to a contract, years that do not extend the contract but are only used as placeholders for the proration. Maximum restructures are typically considered a renegotiation of the contract that requires the player's consent to execute."