He'll not be cheap, but structured the right way, he could help us.
The offer needs to reflect his age and his injury history. As should his usage. Assuming there is mutual interest, he should be paid and used as a part-time 5T end and 3rd down rusher. I'm thinking like every other series as 5T and rusher whenever appropriate.
I will admit, I'd love a Nascar package (ala the Giants) featuring Gary, Z, Watt, and Kenny. Plenty of rush and it wouldn't be an easy front to run against either.
That said, I have no idea how much he has left in the tank or how much he thinks he's worth this point in his career.
EDIT: I forgot to mention contract.
In order to fit him, I'd assume a 3 year deal to give him a suitable signing bonus with the understanding that he is likely cut after year 2. Dude is getting old.