I recently agreed to help a friend with the mechanical work on a 57 Sedan de Ville. Turns out we discovered broken head bolts and cracked heads after we got it to run. Having problems finding uncracked 365 heads. Are the 58-62 390 heads a good alternative? How about the 63 390 heads? Sent from my SAMSUNG-SGH-I467 using H.A.M.B. mobile app