I would use 1 .25 moly Started out with 1.25 alum never had a proublem but I put a post on hey mow to see what they were using all said use chromoly 1.25 EC has them thats all we run never had a proublem and these guys know what there are talking about
I am a 235 give or take 5 or so pounds lol this is all I would run
My two cents
Radar