Need guidance for ordering E34 suspension

I got myself an Oxford Green 535i with a 5-speed manual transmission a year ago and I'm going to order the suspension via AutoDoc

No EDC, no SLS; just the standard suspension with ABS. Car also has A/C (for front springs). Mine was built on October 1987.

I'm thinking about purchasing Bilstein B4 shock absorbers and Koni springs but I have the next question: Are there any difference in shock absorbers and springs depending on production year?

For example, Autodoc offers me two different references of B4 Bilstein shock absorbers for the front axle, with no noticeable differences on the technical sheets of the parts: 21-030246 and 21-031199

What should I acknowledge before making any order? Thanks in advance