Ah, its a manual, I would EOC the crap out of a car like that with a big motor. Makes my 2.2 look tiny!.
P&G is well worth a look, on something like that I would imagine a 100% improvement in FE in the 15-35mph coasting range.
I am uncertain but P&G may be possible in the 35-50mph area as well.
Otherwise the only tip I can offer is drive slow in top gear.
Not sure if this is even possible but the guy next door to me had a 1960's 6000lb carb'd 5.2ltr v8 Dodge utility truck running 18-20mpg highway. (it was significantly worse around town)
He had a 5sp stick and had leaned the carb until his exhaust pipe tips were white.
Maybe if you are carb'd you might be able to tune it a bit leaner. Many 4 banger carb'd cars lean toward rich most of the time so this could get you better FE by being near stoich more of the time.
http://ecomodder.com/forum/showthrea...gts-21369.html
Cheers
Ryan