I've done about 10 of these for 5-luggers that stay on the street, all with great success. I have them down to a science now. It's been about 1 year since I've done one though. I have a special process where I use 4 plates. First I weld the spider gears, then the first plate drops down between the spiders and onto the pin, and it gets welded to the spiders. The second plate then sits in there toward the top of the spiders (basically on top of the first plate) and also gets welded to the spiders. The same procedure is done on the other side. These 4 plates are the key to a strong long lasting job and basically turns the carrier into 1 huge chunk of bombproof metal. I never attach the ground wire from the welder through the bearings, always to the carrier where I'm working. I do use duct tape to tape off the R&P gears, and the bearings...basically anything that will see splatter, however, I heard from a guy who's done many, you really don't need to worry about the crud in there since the hardened gears will chomp it all up w/o any issues, but I just feel better getting 99% of it out. This procedure is so strong I've decided the next one I do probably won't have the spider gears welded to the carrier since the carrier is cast and the weld doesn't seem to stick to it as good as the gears. This is the clicking and cracking noise you sometimes hear when it's cooling. (the welds breaking from the cast carrier) So probably best to just not weld to it. Go enjoy some donuts.