hello im semi new to tri five owner ship. my first was a 55 that i sold befor i could complete it. but i bought a 56 gasser in running condition. my problem is that i bought a wheel set but need to raise the rear to make these wheels fit. it has a 12 bolt with leaf springs no shocks. i have shackles but when i moved it to the bottom hole in hope to raise the rear i still didnt have enough clearance. actually the spring started to bend. so i figure bad springs. i was advised to just add air shocks to raise it. is this a good idea??