Morrison's is pretty open when it comes to the 'formative years'.
We know Clark interacted with Legion, but not about any specific adventures
We know Clark set out after the Kents passed away, but no specifics as to where and what he did
We know he played pranks and Pa even gave him ideas
(Actually, Ma's sort of missing in all this, really, now that I think about it...)
There's room to fold things in, and to have things 'come back' to bite Clark on the bum. Plenty of room for fun