I am hoping to get some advice about starting spelling with my almost 8yo son. I am taking him and my 6yo daughter through LHFHG this year. He is technically 2nd grade and she is Kindergarten. The guide is working great for us, we are just starting unit 22. (a leeeetil behind...

He has worked on Handwriting Without Tears since his 1st grade year. This year, I have him doing the 2nd grade printing book alternating with the cutting and pasting books scheduled in LHFHG.
Anyways, I can see that in HOD they advance from the letter writing books to the spelling lists. I am wondering if I should start him on list 1 from Beyond (already have it) instead of the handwriting practice he is doing in the HWT book? Not sure if that is necessary and I should just wait so he and sister can start together in Beyond. She would start list one and he would probably start list two.
I am also wondering if it would be beneficial or necessary for him (and her) to go through both lists of spelling words or not? He doesn't really know how to spell very many words (he can read them without any problems). I don't know if the schedule allows for students to go through both spelling lists at some point, or if one list is enough to move on to the next guide.
Should I start him on list one now and finish the 2nd list when we get to it sometime next year as we go through Beyond? It would mean following the spelling schedule separate from the rest of the guide. I don't want to push him too fast, but I also don't want to keep him from spelling skills that seem normal for 2nd graders.
Thank you!