Tips for repairing exhaust manifold. help

94 4.0 auto np231.
June 2015 115K i replaced my manifold since the old one failed at the 1-2-3/4-5-6 colector merge. this was the updated style with the acordian tubes located on the 1/6 tubes.
Fast forward to now 136K, it's cracked again at about the same spot.i can hear it( nagging tick that gets worse under load) the old gal is getting much needed attention, which inclues 4.5 lift(3" currently) new rear springs (Rc AAL currently, sucks.) new schackles and new control arms since all the rubber bushings are dry rotting. New shiny stainless ehhuast is planed as well since Ohio has deceded to attack it with salt and my tail pipe refuses to cease it's percentant rattle.
I have the old manifold and would like to know the best method of repairing it. the Crack is about an 1-1.5 long near the weld at the colector
i have acces to a few diffrent welders, mig tig and stick. i am familiar the the use of all three machines and have had some practice, most familiar with mig. i know this is a band-aid and should really be replaced but currently it's easier and cheaper for me to weld the one i have and run it. this is my daily and i can't afford to have it down for any extended periods of time, hince why i would like to repair my old one, and swap when time allows.

Thanks Chris

Stop drill + weld. Ive done them with mig, adding a reinforcement gusset/plate. They last a while... but theyre gonna crack again somewhere else.
TIG is probably ideal if your crafty.

If you have a junk 4.0 head, bolt the sucker to the head, and keep the heat down.

No exhaust manifold will survive if the motor mounts are worn out. While you have the manifold out gives you tons of room to replace the motor mounts.

Mounts will be replaced with the new manifold. The repaired one simply needs to last still spring, or as long as it can then i'll deal with it then.
Only problem I see with tig is the rust and crap that I can't get out. I know tig does not like dirty metal.
Thanks for the help.

Repair your collector. Put a flex coupler in place of the crossover pipe.

I've repaired three so far, four if you count the one I did twice. The first one I did on the bench and I had some trouble aligning my bolt holes when I was done and it had a little bow in the flange. Likely the reason I had to do it again after a couple of years. I likely stressed it in some odd ways reinstalling my slightly heat warped results.

The next three I clamped the flange to a nice flat piece of I beam I have in the garage, with as many big C clamps as I had, maybe six. Worked out great, holes lined up and the mounting flange didn't bow.

Both of the last two lasted longer than the original. I used mostly a MIG. Practice makes perfect.

Technique was a little tricky. the manifold material is some kind of alloy, not pure steel. Hot, a little hotter and then too hot is a pretty small window, kind of reminded me of stainless, likely some nickle in there. Letting it cool, re clean and doing a short bead and repeat, worked out better than trying to run a continuous bead. Like mentioned, drill a hole at the ends of the crack. And in my opinion don't pile the weld on too thick, dissimilar metal thicknesses, bonded together, tend to expand and contract at different rates. You may end up with a new crack right next to your weld. Like my first try.

Where the pipes meet going into the collector, I pilled it on pretty good almost like a gusset, seemed to last well. No issues over time, it lasted well.

I'd weld one spot with the MIG, kind of like a spot weld, make sure it burned in well and flowed a little at the edges, clean it up again and repeat until I had the crack covered. Then I could run a bead left and right of the crack and over the spot welds without much issue. I'd stop often and wire brush the soot off. Like I said temperature control was a little tricky. Instead of trying to adjust the temp knob on my welder, I'd stop welding when it seemed to be getting too hot. A couple of small mistakes and got my timing down.

Were the pipes come together into the collector is rough with a MIG. I've done it with both a MIG and an Oxy-acetylene torch, Doing it with the torch was definitely easier.

The last time I had to take it off to replace the snapped bolts in my motor mounts, I pre ordered a new one, I didn't need it, I put it on anyway. The repairs held up fine for well over a hundred thousand miles. I have a spare on the shelf now.