The F28 is going into my Astra 3 chassis. I appreciate I have to use the old F20 mount/casting and modify it or the gearbox to get it to sit properly.
The only thing I don't like is-
The bolts that will go into the F28 are not half as big as the original F20 ones. Also, two of the 3 holes need tapping to accept a bolt.

Is it ok to use the smaller bolts as it's an engine mount after all!