The windshield washer on my '84 760 hasn't been working that well. I bought new rubber line at the dealer, a new check valve, and replaced the washer jets with the later style (two opening per side). I found a used washer tank with pumps off of Ebay for $12 including shipping. I think the pump on my old setup might be the problem. Anyway, my car is a sedan and the replacement tank/pumps came from a wagon (hence the two pump setup). Is it okay to use this larger reservoir in place of my old one and just run one pump? Also, how are the washer lines routed? It seemed to me like there used to be a line coming from the tank apparatus that didn't go to anything. No fluid came out of this, so it appeared to be just a vent line. I want to make sure I have this setup correctly.

Thanks in advance.
Dave