I'm building up my '79 Blazer and am rebuilding the front axle. I currently have an open-diff. I would love to have a selectable locker or even a posi, but I don't have $500+. If I weld the spider gears to spool it how bad will it's manners be if I only put it in 4WD when it's nasty out? I just don't have any experience with anything other then an open diff in the front so any advice about any other kind of diff or experience would be appreciated.