Remeber that these things need to be installed while you're building. Plan ahead. Plan to install them before it get too cramped, and you foresee ripping things apart! (that's obvious...)

the plans should indicate the 'reccomended radio gear loaction'. Go with that for the servos. the Rx and Battery can be moved around as needed. Try to position the servo tray on the CG if you have to guess.

Tanks should be removable, so, plan to be able to remove it. Don't forget the foam padding around it.

I usally test fit the tank as the fuse is being built,and at some point the decision is made, when and how to insert it, and the path it'll follow when removed..

Always save the covering for last. The your table and tools are clean, adn you can concenstrate on one aspect of the building at a time.