I have the stock stamped steel non-adjustable rockers on the shaft. I'll go back tomorrow and go through the procedure again, making sure I'm starting at base circle.
I answered you PM on the base circle question and valve overlap.
If you are using the same rockers as before, then a length change of 7.500" to 7.125" does not make sense.
They may change a bit with the individual heads, but I cannot think of anything in the 302 heads that is so different that the pushrods should change so much.
The cam might be a bit different in base circle, but really should not be anything like that.
The valve could be waaay too long but that would mean they are basically wrong.