910 struts will nearly bolt straight in. Change the strut tops, and get some rings machined up to key the 910 struts to the 310 steering arms.

PM FIGJAM, (Warrick). He is in CHCH.
He is putting a Z20 into a 1200 two door sedan.
He is fabricating a whole new tunnel/floor pan.
However the 310 have quite a large tunnel already. (I am fitting an L20b into a 310 coupe real soon. they may even use the same gearbox.
the only real challange is modifing the X member. Yoiu may have to recess the top of the X member to get the motor low enough to clear the bonnet.
You will also need a "frontsump" .

Converting to a hydrolic clutch is simple on a 310. I will have to show you mine when it is in.
I wouldn't dream of trying to go cable for this swap.

If you jave the whole car for the swap, it should be easy if you have acsess to some engineering resourses.

We'll have to catch up sometime.

Bart.