A good commuter engine is the Mercedes OM617 5 cylinder turbo diesel and it can run on alternate fuels. Kit is a drop in and bolt up.
It will run highway speeds with the 1.6 T-case, but 1.4 gearing is optimal.
Easily pulls 70MPH on the flat.
The only reason for this post, a member has cold feet on their conversion and has a good engine as well.
I could put you in touch with the member with kit and good engine if you PM me.
Uncle "Richard" Douglas has a Land Rover with big wheels that never gets stuck... until he breaks something so it won't go. Uncle Douglas always breaks something. - Anna Crowther at the Conclave 2012 (AKA Carburetor Neck)