I have just purchased a 97' E420 Sport with some Kleemann upgrades and I want to buy some new headlights cuz the stock ones are all beat up. well every time I go online and try to get them, the descriptions say "will fit all W210 E-Class".So I need to know is W210 just another way of saying E320,E420,E430 and E55 or is there really a big difference. For some reason I'm thinking W210 are Diesel powered but I have no clue. Also every time I type in W210 in the search image it brings up Benz's that look just like mine. please advise.thanx. Only serious answers please

Your car is a W210. All E-classes that year are W210s. While the primary difference is engine size that is certainly not the only difference between models in the W210 range.

I have a W210 E55 AMG and there are some major differences, including suspension parts, tires, wheels, brakes, leather quality, exhaust, trim, ride height, among others.
You will be fine with a light that fits all w210s, but for future reference if you add other parts there may not be universal fits.