The 1998 Jeep Wrangler wiper blade sizes are 13" wiper blades on both sides front and a 18" rear wiper. See sources and related links below for more information. Since there are over 22 different wiper arm attachments, do not buy wipers just by length only - be sure to lookup exact wiper blade part numbers by vehicle make, model and year for the brand wiper you decide to purchase. This ensures correct length AND correct attachment.
Fuse or windshield wiper motor.
Windshield wipers not turning off is not a common problem in the 1997 Jeep Wrangler. Remove the windshield wiper fuse to turn them off.
Your wiper arms that run from the wiper motor to the windshield wipers may be binding and need to be replaced
The 1998 Wrangler Owner's Manual indicates it is fuse # 14. If that looks OK, you may try briefly, manually moving the blades gently with the wipers turned on - there may be a slight linkage binding or "flat spot" in the motor.
Yes, Fuse panel under the dash, drivers side fuse #14 I think
A 1998 Jeep Wrangler does not have EGR.
Trim package
no it will not, the frame is slightly smaller in the earlier jeeps
how to change the windshield wiper motor in a 2000 jeep wrangler
between the hood and the windshield
MOTOR FOR WIPERS
Yes