Thats a great photo! I dont pull much weight anymore, boats in the 6k range. I do a lot of highway driving at pretty good speeds. We have pretty high limits and cruising in the 85 range barely keeps up with traffic at times. Trutrac is a great diff; I have one in my Nova. did you leave the front open?
https://www.chevyavalanchefanclub.com/cafcna/index.php?threads/456-re-gearing.158924/

