smooth cowl , and aluminum bed floor question

[sodak69c10]

question#1 i'm sure there are some post some where on how to do this but i was wondering the best looking low buck way of how to smooth off the vents in the cowl and then where or how do you feed air to heater core after said smoothing (can it pull enough air from inside the cab though the kick panel vents?)

question #2 i have a chunk of aluminum diamond plate and was thinking bout replacing rotted wood bed floor how can i mark the bolt holes and spac it up so than it same thickness as wood , or is there any where i can get new wood and strips from low $

p.s. i not very good with body work but i trying to learn