Sorry for the late rely, I'm struggling with having a propshaft done, aluminium oil sump welded, and steering column extended, so I've been busy on other battles
Regarding these engine mounts, first, thank you very much for the replies and the links, very helpful.
But now, I am wondering if it will be a good idea to use them finally, considering they are 45mm lower then the Sierra ones, which will drastically reduce my ground clearance if I don't change anything to the chassis engine mount boxes (EM plates), or make my own engine support to replace the original cast ones (and I would like to avoid such a thing).
Now, with the shorten oil sump, the MT75's bell housing bottom part ground as much as possible, and the 80mm high Sierra rubber mounts, the sump sticks out 35mm under the bottom rail, which is good. With the Land rover rubber mounts, it will be 80mm under the bottom rail, which looks way too much.
On another hand, it will be good if I could lower the engine a little, because it looks like the big air intake manifold will be difficult to fit under any bonnet the way it is now.
So I'm waiting for my oil sump to come back from the welder and will make new "simulations".
Thanks again.