Another option I used to secure my Warn Enforcer winch bumper and Warn 12000 lb. winch to one of my prior 4Xs... . after torquing the mounting hardware I applied JB Weld to the exposed bolt threads and nuts. As most of you know, this stuff sets up like concrete. The rationale behind NOT using the tack weld method (in this instance) was bolt strength. You WILL compromise fastener strength if you tack weld the bolt AND/OR nut. However, strength may or may not be an issue with your specific accessory or its intended usage. Just wanted to warn others that may be mounting a combo brush guard/winch mount... . strength is paramount.
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'98. 5 2500 QC 4x4 Sport, Glasstite Vision II, 285 BFG A/Ts on M/T Challengers, Warn 4X Boards, Mopar fender flares & tow hooks, NW Custom s/s-rubber mud flaps, Mag-Hytec diff. cover & trans. pan, Edelbrock IAS shocks, Reese Titan V hitch, VDO Vision gauges, Dynamat, '00 Sport grille & valve cover, '00 Sport headlights/PIAA Super White bulbs, PIAA Dual Sport 900 aux. lights, BD exh. brake and TorqLoc, Prime-Loc, Amsoil Dual Remote Bypass, Optima Yellow Tops, Bosch 275s, VA CPC, (censored), Aeroquip braided s/s fuel lines, Banks 14 cm2 turbine housing/Big Head wastegate actuator, ATS 3-piece exh. man. , Banks 4" dia. s/s exh. sys. , BD V10/Cummins hybrid TC & valve body, BD trans. front pump & PressureLoc, Air Bulldog induction hood (with NACA ducts), plus MANY other trick modifications