I have a 79 12 bolt rear diff with some sort of traction device in it (which doesn't work), I believe it's factory "gov-loc" limited slip. Haven't had the lid off in years, but I wonder if anyone knows If I can insert a MINI-SPOOL inside the Gov-Loc, or diff carrier at all?

no. open carrier only.

no. open carrier only.
shit. That's what I thought. thanks.
Anyone have much luck welding them up?

yup

You could weld the spiders but I'd be careful. What sized tires are you running? Lot of HP? I wouldn't start dumping money into the 12 bolt. Search around and see what is available for upgrades within your budget.

Buying a red star will help in the searching and help the site.

Thanks you guys. I am of the mind to not spend lotsa bucks into either the front nor rear axle. Right now my sits at around 4000 lbs & I plan on keeping it as light as possible. I have also switched to a very narrow rim to work with narrow tires. Currently running 34x9.5 ss.narrow super swampers. may go taller (35.5"x10.5").

yup

Would you mind sharing any advice as to where to weld? Perhaps filling me into what tires you run & type of wheeling you've tried?

weld the gears together, weld the gears to the carrier.

what gear ratios ?

i have a fully welded 3.08 carrier, i think 3.54 3.42 also use this carrier, not 3.73

weld the gears together, weld the gears to the carrier.

what gear ratios ?

i have a fully welded 3.08 carrier, i think 3.54 3.42 also use this carrier, not 3.73

Hey Man,

That would be really cool. I'll give ya a PM.