No they will not simply plug in.
I installed a set of the 98-02 power/heated mirrors on my 95 (same as your 97).
I cut off the connector from both mirrors and since the wire colors don't match, had to spend time tinkering with wire configrations and spliced the old connector to the newer mirror. I soldered all connections. Once you figure the wiring out they work perfect.
There is a separate 2-wire harness coming off the mirrors for the mirror heaters that you'll have to get creative with if you want the heaters to work. A lighted switch, relay, and a bunch of long wire should put you in business. The factoy 98-02 heater setup has a timer built into the system, you truck doesn't have it, so you'll have to remember that you can't run the heaters more than 4 minutes so you don't crack the glass.
-Mike