One thing to remember..not ALL gassers had their front ends raised high in the sky. There were plenty of gassers that kept the nose at around stock height. And ditto for the straight front axle setup...they ALL didn't have them. And if you wish to be accurate height wise, the engine crankshaft centerline could be no more than 24" above the ground. Translated into a model that would be pretty close to one inch. So if you raise the front end WAAAAY up in the air and your engine crankshaft centerline is up more than an inch...it would be illegal. As an example..look at Burnout's post just above of his beautiful black Willys...it's pretty level.
Everything that Niko posted above was taken directly from the late Byron Stack's superb gasser website...Gasser Madness. Go to www.gassermadness.com and look around...you'll find lots of photos and a ton of inspiration.
If you want something specific as to the gasser rules, just hit me up...I have some of the old NHRA rulebooks. Be glad to help ya out!