Greetings... new to this site. Have a stock 98 and want to put some side skirts on as the bare frame looks really bad.

Guys... plese help a rookie with some info... do skirts fit stock 98 with ease ? What is the average pre shipping cost for used skirts in good shape ?

Secondly... Car is a 5 spd man. 4 banger... any tips on improving performance and mileage ? Not trying to make a race car obviously as it is the 4cyl. but would like to improve as it is very sluggish going up hill. Have to really wind it up.