e34 530 vs e34 540 clutch kit and diff ratio?

[Mohamed 525i]

Hi guys

I got e34 540 with a 530 manual trany (5 speed) and it is vibrating on 1st gear, my mechanic said it is coz the 530 clutch is smaller than the 540 .

so what is the best clutch kit u guys suggest to go for and is to be the 530 or the 540 kit ?


also I have the diff. ratio 2.93 so what is the best swap I can get
(when it was auto at 140 speed the RPM on 2900 and now it is more than 3200 ) any suggestions please ?

thanx


regards

Mohamed