Preventing corrosion during a build?

Any motor oil, gear oil, or even grease wiped on the surfaces occasionally should suffice. If you want to go for long term protection, LPS3 has worked very well for me, it resembles Cosmoline. WD40 evaporates and leaves the surface vulnerable to corrosion at some point. If it is an unheated garage I recommend covering with a blanket or tarp of some sort and run a 30-60W light bulb underneath the cover all the time. The little bit of dry heat will drive away moisture as the humidity changes, especially in the spring when it is cold at night and warming and more humid during the day. Iron sweats and then starts to rust.