Shift knob jump

Hello everybody
Maybe someone can help me:
I have an Euro 1988 E30 M3. I changed the bellow-accordion under the manual shift knob (inverted one: 1st is down left); I placed the original one; however after checking and checking I can not fix this problem: "driving in 1st, 3rd, 5th, that are down; the shift jumps to neutral and have some vibration"
Thanks

Not sure what exactly you changed. Sounds like the shift lever isn't lining up correctly. Have you checked your motor mounts and tranny mounts?

what did you replace it with? A pic would help. Sounds like you used foam from an e36?

your shift linkage is on wrong