Not to worry Ira!!! We're all in that same small boat ...hahahahaha
My somewhat unorthadox methods include obsessively over building everything ... I always go crazy for structure, and little "frills" ... so the extra inner framing is for just structural needs ...
I will have an airfoil shaped panel over my upper splices on the outside , the excuse being an awning mount , besides structural ... I'll have a similar smaller panel on the outside of the driver side rear , also at the splice ... my excuse , a flagpole mount ....I know it's gonna be heavy !!! The trailer weighs a ton and was made for a fairly large boat so my stuff won't be THAT heavy ... Trailer is 8' OAWx18'OAL... big boy huh ??? May have to cut it down later ...after the next hurricane season (It is primarily an escape pod/BUGOUT) Cabin/Galley is 74"x12' ....trying to keep all the weight aft too since the tongue weight's gonna' be killer on the old back , and truck ...
My Pal Bob came by today and we put the frame and floor together with the construction adhesive and 2" screws every 12"...Pics as soon as my battery is charged... or the sun comes up , whichever comes first