27mm torsion bars and super sport springs
fwiw, 27mm torsion bars are stiffer than grant indicates and the rear springs are softer.
imho, wheel rate is the only way to measure this stuff. that is a measure of the force required to raise the wheel an inch. on a specific chassis, wheel rate is wheel rate - takes spring location/angle out of the equation and gives the net result.
short bars (milano & late GTV6) have a wheel rate of ~ 294#/inch. long bars (alfetta & GTV6 to mid '85) are ~ 274#/inch.
the SS rear springs are ~ 140#/inch.
imho, there is absolutely no tangible benefit to spending the huge $ required for an RSR suspension.
if money is a consideration for you - buy JJs used 27s, throw them in and enjoy your car.
in my experiences, you do need a stiffer shock to adequately control the heavier springs - but if need be, you can get by w/ stock units until you can afford more.
as to F/R ride height - best way to set is to corner weight the car. if that is not easily accessible for you, good rule of thumb is to set rear 1/2" - 1" higher than front (measuring to the bottom of the jack points, if you still have them, is very convenient). will be close enough to give satisfactory results. w/ a limited budget - easiest way is to work off the rear springs final ride height. measure rears, then set front ride height to the desired spec.
don't forget to realign front when you are done - since this sounds like a mostly street car, probably smartest bet is to set camber to negative end of the alfa spec for your car. will give good results. of course, can go more negative - more negative you go, better handling and cornering, but soon you cross into severe tire eating mode - which for most guys, just plain does not make sense on a street car.