Building a 1911 is nothing like an AR - that's just assembly. AK is a little more rigorous, but nothing like a 1911. There will be no presses or hammers used. Building a 1911 is machining. Lots of patience, files, sand paper and stones. Or an endmill and other tooling for sight cuts. Also, there is no such thing as "drop in" on a 1911. If the part does "drop in" it wont live for long and likely wont preform all that well.
ETA: before the die hards jump all over me, yes, some parts do just drop in. Main spring housing, hammer strut (sometimes), trigger (sometimes), recoil spring, hammer spring, recoil plug (sometimes). The major action and control parts, however, do and should not.