I have a 1988 YJ. I got a quote of $900.00 for parts and labor ( new pressure plate, clutch disk, slave cylinder, pilot bearing) from one shop. Another shop qouted me a labor only rate of $600.00 if I provided all of the parts.
Preen is a pre-emergent weed prevention product. It prevents weed seeds from germinating instead of killing existing mature weeds. Preen works on a wide variety of annual weeds, but it won't have an effect on perennial weeds because they already have established roots.
To preheat is to make something become hot beforehand, especially an oven before you bake something in it. Frozen pizza tastes better if you preheat your oven before you cook it. You're most likely to find the verb preheat in a recipe. You might want to preheat your grill for a certain length of time before the guests show up for your barbecue, or preheat your oven before baking a loaf of bread.