Can any give me some guidance on the best way to get access to the crowl (air venting to the cab below the windshield between the wiper arms) I have some rust issue inside i need to deal with. I will be pulling the dah and the fron clip so any advise wouls be helpful

 

The cowl is a balloon assembly. There is no access unless ya make yer own. Depending on where it needs repair, I'd wait til the dash is removed to develop a game plan lest ya make unnecessary work for yourself.

 

that what i thought need to replace the floor pans i am fearing that it is rusted throw and leaked water inside over time. Thats why the floors ar so gone and the rest of the truck is mostly rust free. I can see pin hole from the grating

 

Ewwww. But I can totally relate. My 65 Mustang has a rusted cowl and need to blow it open .

That balloon assembly is one of Ford engineers' worst designs. In this case, GM's removable cowl panel is superior...

 

I will post pictures when i get into it
I saw what the you tube Guy my friend pete had to do to get to the 68 mustang he was working on not fun. might be easier to get a different cab
if . bur if i can get in from the back side and the top is not rust i think i can handle that but pullin that body peace off and then getting it back on is not something i ready to try

thich i can get whole cab from the local pick n pull for $500

 

I will post pictures when i get into it
I saw what the you tube Guy my friend pete had to do to get to the 68 mustang he was working on not fun. might be easier to get a different cab
if . bur if i can get in from the back side and the top is not rust i think i can handle that but pullin that body peace off and then getting it back on is not something i ready to try

think i can get whole cab from the local pick n pull for $500

 

Yeah, that design wasn't one of Ford's better ideas.
I wouldn't necessarily assume that the cowl is leaking because the floor pans are bad, Floor pans can rust out really bad for problems not related to a leaking cowl.
Here's what's behind the dash. Except for where the wipers pass through the cowl and two access holes on each end, its pretty much sealed.

 

Also notice in the pictures, the cowl is a lighter gray than the other metal, that's because the steel that's used in the cowl is galvanized.