Larger gearbox tunnel, drive shaft tunnel and diff tunnel.

fabricated ready for you to cut your old one out and weld in, complete front tunnel, through middle and larger above diff - 3 pieces

front tunnel - 600 long / 280 high at front & 200 at back approx / 280 wide at front and 150 at rear on top side 

If just using front there will be a step to fill in to original, some fettling required

Front EF1964 $185 plus gst - full set EF1964/1965/1966 $345 plus gst