Starter Met H2O...Water Won

[PolkLandbruiser]

When a starter comes in contact with water, what are the two (or three) components most affected? I've been told that the plunger and contacts are usually what need to be replaced after it shorts out from being submerged in a lake. Anything else? I know i always pay the local shop $40 to perform the work, but figure i got the same tools, so why don't i save my $.
This is a starter off the 3FE in my 62.
thanks to all.