Reduce the weight. Weight is the biggest enemy of performance as it effects acceleration, braking and lateral movement. At 2490 lbs the stock Scorpion is a lead sled. Weight can be reduced by upto 400 lbs without much problem, especially if you can get around emissions and live in a climate bearable to not having A.C. or as in many cases, the A.C. doesn't work anyway. My car weighs under 2100 lbs and includes some extra items like an oil cooler, twin carbs, and fire suppression equipment. Use Montecarlo bumpers, either Montecarlo euro-headlights or Beta dual headlight conversions, replace the very heavy stock seats with racing seats, replace troublesome power windows with manual window regulators, and so on. If the A.C. is removed, use an aluminum oil filter housing which is 13 lbs lighter than the cast iron original and remove or rewire the A.C. fan on the radiator to run with the cooling fan. Weight removed from the engine itself will put less strain on the rear crossmember, probably the most integral part of the car with such a vital role I will include as my next modification.(2)

Front end float at speed? a front spoiler helps as does one size smaller front tires. (1)

Scorp's are typical FIAT products so that most mechanical parts are usually common to other models or manufacturer's. (1) 

Been talking to Bernie Benz who has some really clever solutions to all sorts of problems. I'll list these and you can call Bernie for details. He has fixed:

His phone is 415-854-4907 and he seems to love Lancias. (1)

Gas cap. Disassemble, clean and lube. The original gas cap. They are unavailable. All it takes is undoing the large lock ring on the inside. There is a spring so be careful. Always lock it as they have been known to develop legs and the replacements do not have the cone sides. Iap, in va. Has a cap that fits an Alfa GTV-6 that is identical and fits except it has three spokes in the center instead of the scorp. bar. (1)

Velcro/silastic works great for holding down the trim panel under the rear window. (1)

A bungee cord from your garage ceiling will hold the engine lid in the vertical position for a lot better engine access. (1)

Caribou has tops and repo hood/deck release levers. (1)

Save all cores for rebuilding as someday they might be all that's available. (1)

Relocate the fuel tank. Relocate the fuel tank to the luggage compartment. This mod is a little extreme but provides a better front to rear weight ratio, easier engine access and room in the engine compartment for "go fast goodies." I mounted a 15 gallon fuel cell, the fuel pump and a variable fuel pressure regulator up front and still have room for a small weekend bag and my tools. I mounted the fuel pump to the front bulkhead near where the brake and clutch lines come into the luggage compartment. I added a toggle switch to the fuel pump sticking back through the bulkhead so the switch is above the pedals. Thus I now have an anti-theft/ fire protection kill switch I can reach from inside the passenger compartment but hidden from would-be car thieves. The variable fuel pressure regulator is a great modification as allows adjustment at the turn of a knob which can help when tuning the engine or to better your gas milage while driving around town but allow you turn it up for days at the track. Be sure to vent the fumes to outside the luggage area. I located an oil cooler where the fuel tank originally was located. Don't be surprised when the gas station attendant runs over to see why you're pouring fuel in your trunk. If you prefer not to make this modification you may still wish to increase the weight over the front wheels as Scorpions are notorious for front brake lock up partially due to the poor front/rear weight ratio. Other ideas are carrying your spare up front or filling the luggage compartment with extensive stereo equipment. I also bolted a plastic battery box like those RV trailers use to the luggage compartment floor. I no longer have to worry about battery acid eating my battery storage area but also lowered and centered the weight of the battery. (2)