Travel and see the world from a Mercedes Benz

I wanted get help with a 91 300ce I bought. The car ran fine while I was trying to get drivers seat to work which was the module under the seat and hard to find. The started running rich and running rough, so far I’ve changed plugs, cap & rotor, injectors, EHA vale and fuel filter. I didn’t do a fuel pressure test because I’m not sure where to hook up and probably don’t have the correct fittings. The car right now idles ok but won’t accelerate in drive, bogs right down. Pulled the plugs after recent start up and found cyl 1-4-6 not firing well while 2-3-5 are. Compression test was good with a high of 140 and a low of 125. I hate just changing parts and don’t have a lot of experience with these cars. This is a California car that is rust free and gas 158,000 miles on it . I have no problem making a donation for any help you can give me. Thanks