I got stringer problems!

[Vic]

I bought an 84 steplift last year. It's been converted from the old Cdrive to a nice swimplatform with o/b 175 merc, its a supper boat. Doing winter touchup maintenance and pulled the stern livewell completly out thing about doing pourfoam in the V of the hull with some plumbing. Just realized today that mt stringers are soft. Has anybody ever lifted the cap off of the back and tackled this one? Man I could use some suggestions.