Autoload plus extra configurations

[Eric]

I'm shifting a bunch of libraries to autoload in order to reduce load
times, and running into an issue with extra configuration for those
autoloaded libraries. Tramp, for instance, is enormous and slow and I
don't use it often. I want to autoload it, but I've also got some
extra configuration that accesses tramp-default-methods and tramp-set-
completion-fuction, which are unavailable until tramp is actually
loaded.

Is there a way that I can tuck these configurations inside a hook that
runs only when tramp is actually loaded, or otherwise delay the
evaluation of these configurations until the proper variables and
functions are available?

Thanks!
Eric