My parts truck has a 350 in it that says Goodwrench 350 on the valve covers. The previous owner told me that it was installed in 1999 and was a 4 bolt main 350. I tried grabbing the numbers off the block to see exactly what it was but I couldn't get enough acess to the numbers to read what they are. Anyway, what are the chances that this motor is a 1 piece rear main seal and is also a 4 bolt main? The truck was originally a 1985 350 carbed. I doubt that a motor installed in 1999 could be a 2 piece. Think this motor would be worth rebuilding and using as a power producer? Wjat might be the stock numbers that this motor produces stock?