Theres a guy at toobing/music , but I don't remember any plans.The ice chest boom boxes I saw are marine speakers and radio witth battery inside held in with small wood braces .I haven't seen the solar yet ,good ideal thu.
I remember his had stand up speakers ,but I like the ones built into the top of the chest.Good luck I' starting on my daughters ice chest and hope to have it done by end of July 1st of August.
srds
Good Camping