And ummm, i dont know if its the picture or not and i hate to be a nazi about it but i would reconsider those welds on those perches
I noticed that as well, looks like a lot of splatter with no penetration. I hope you feel comfortable with the additional passes, but this is certainly one place you don't want a weld failure!
Good job on the puller, a nice bit of ingenuity you used there. I'm jealous of the rear locker, I'd like to add a selectable to the 8.8 to run with the Spartan I picked up for my D30. As far as the plug welds go, every 8.8 I've done had the same plug welds. The first one I converted I simply welded the pumpkin to the tubes with solid .045 MIG wire on a Lincoln Power MIG 255, and never noticed any cracking. However, the one I am doing now, I will be using a nickle rod out of my DC stick machine and will be doing pre/post heat. The thing to remember, you don't need a full circumference of weld bead to keep the tubes from spinning, especially using a 4.3L V6. You can get by with a few short beads, which should control some of the heat, and will be more than enough to hold.