Very nice. I have an 84 300d and the transmission is controlled via vacuum and a cable. Definitely important to verify the integrity And specs of the transmission vacuum system if it has that sort of system. I’m unfamiliar with the 190s
I ran a 1989 190e auto for 21 years, Assuming a similar bowden cable arrangement as the diesel, mine was adjustable so that I could fine tune the way the transmission changed up. Worst aspect of the 4 speed transmission was that 1st gear was so low that it started in 2nd and was effectively a 3 speed for 99.99 percent of the time which was rather a waste. A ridiculously low 1st gear was an MB trait that continued all the way to my current MB.