68 Z motor mounts

[68Zproject]

I'm confused again after reading some posts on the MM issue with 68's and 69's.  I have the original frame mounts on my 68 Z28.  I have a '70 CE 302 in it.  The engine mounts that came off it said made in China so I got the engine mounts at Rick's for the original frame mounts (EP89).  Is this the right set up for this combo or do I need to get different engine mounts?  I've got a lot of vibration over 70mph that is speed related and not RPM.  I've turned the u-joints around to no avail.  Thanks.

[Gramps69Z]

Did the virbration start after changing the motor mounts?  A high speed virbration sounds more like a wheel, tire balance problem to me.

[68Zproject]

No, the engine was rebuilt so I didn't go too fast until I got some miles on it.  It could be all the above, its just really vibrates in the transmission area.  I just want to make sure I have the right set up for the motor mounts.  After reading posts and the info CRG has about the incorrect engine mounts causing vibration etc., I wanted to rule this out and then go to the driveline.

[firstgenaddict]

Sounds like the tailshaft bushing in the trans... if that is what you determine it to be... take the trans out... I did it in the car... next to impossible...

[68Zproject]

Tranny inside is all new.  Still wondering if I have the correct motor mounts.

[68Zproject]

Does anyone know if the EP-89 part number motor mounts at Rick's, are correct for 68 Z with original frame stands?

[68Zproject]

It was the driveline out of balance.  I changed the yoke and that threw it out big time.  I got it balanced and took it up to 90 with no vibrations.