Product review (5 stars): looks like I'll be ordering a 5A motor soon
Correct part for my FTQ387LWGX, works for the top or bottom fan the middle fan is the DG31-00005A.  The original part numbers taken from the side of the motors are SMCU386B (top or bottom), SMCU386A middle fan.

No real concerns with the replacement, 2 screws hold the cover (for the fans) on inside the stove oven, 7 (I think it was) to remove the panel on the back of the stove, 3 screws to remove the motor and bracket (after the back cover panel of the stove is removed), and 3 more to remove the motor from the bracket. No soldering, a pre-wired plug in clip is included as part of the replacement motor. Do note which way the color of the wires are attached to the connector, it didn't look directional. The fan would still work but it might spin the opposite direction if the wire connector was attached backwards which might be important in a 3 fan set up (push air or pull air).

Before removing the motor, the fan blade has to be taken off from inside the oven, as mentioned above 2 Phillips screws to remove the cover over the fan blades. I didn't note the size but 1/4" drive socket set will do the trick to remove the nut on the end of the shaft holding the blade, Righty Tighty, Lefty loosey for this fan, hold the fan blade (glove advised) when loosening the holding nut, The blade is shaped to fit the shaft for orientation  and there is a spacer that goes between the motor and the blade, motor, spacer, blade, holding (cap style) nut, this might be specific to my model number.
There is also a little cup (kind of a washer that goes on the motor shaft, you will see it when you take stuff apart, just move it to the new motor.

This is not a difficult job and no reason to spend money for a service call. Do unplug the stove from AC before disassembly and if you have any doubt about which motor is making noise, remove the back cover panel on the stove, run the stove (bake mode seem to be the best) and listen to each motor by placing one end of long handled wooden spoon on the back of the fan motor and one end against your ear. The top fan was the problem in mine but the middle fan is a little noisy, looks like I'll be ordering a 5A motor soon.

All in all time is 20-30 minutes depending on access to the stove.