Im kinda new to building, I have built two Great planes J3 cubs without much problem at all.
My wife bought me a Pica 1/5 scale P51 kit for my b-day and that is another story. Have read this kit is for advanced builders, seem more like a box of wood with little directions if you ask me. I have many questions and the directions do not give much if any detail/s.
I purchased a Moki 2.10 fir this plane and robart 5/8" strut air retracts, after abit of shaving on the top front of head the engine fits perfectley under the cowl with side exhaust. I opened the fuel box area to now except a 32oz. tank instead of directions reccomendation 16oz.

Now i'm at the stage of installing the retracts, the retracts came with no directions, are they suppose to? I got the air bottle kit but don't know the best place to mount it and how the lines should be routed in case I need to excess them for some reason later. Yes I have a diagram but diagram says nothing or give tips or hints to answer my question/s.

My tail wheel air retract looks so far from going in that Id have to completely modify or build three new bulk heads in the back of the plane just to mount it, is this sometimes normal?

Anyway, back to my question, Is there a reference book that has can help answer alot of the questions I have?
Or would asking questions here be more helpful since each plane may have a different answer for certain procejure.

Thank you in advance for any help...