Chuck Schuldiner's picking technique

Recently someone asked me about playing some Chuck Schuldiner solo’s, which I found an interesting idea, so I got to work. I had not listened to his music for about twenty years and I seem to recall reading in several places about how Chuck was a strict alternate picking type of guy (I know, heard that one before…). As far as his rhythm playing goes, sure I can see that. In the Crystal Mountain solo, just after the tapping part and the first melody, it starts with what I am pretty sure is an economy picking lick (all downwards). It then picks up a short melody, a fast alternate picking part and then again what I believe is an economy picking lick (all upwards). It may be possible to alternate pick it (it is not hyperfast, but firmly in the shredding zone), but currently I just do not think it is.

The Story To Tell solo is a bit tougher still. It has this melody part first after which he plays what seems a two string pattern on b and e (at around 2:45). The first five notes of the pattern feel very much economy picking to me. I initially thought that he played six notes after that, which made me struggle with the second part and landing my pick right, but if I listen closely I think it is simply a mirror image of the first part, so just five notes with economy picking in the opposite direction.

Just really curious if anyone else has worked on these solos and what their findings were. Could not find a lot on Chuck via the search function (it may just be me). If I am being vague in my description, let me know and I will try to explain it better.