need opinions on frame

[Aftermarketfreak96]

I have a 1987 chevy k10 and am in the process of sanding the frame and painting it, and when I removed the frame shackles they were somewhat pitted on the front two, and dented a little. On the drivers side frame rail where the shackle mounts, i hit it with a hammer a few times and it bulged in about a quarter inch or so(this area had a lot of rust flakes on the inside rails). So far we ended up hitting the dents out with a dead blow hammer to even them back out. On the far back passenger side it has rusted through, just below where the rear shackle mounts to the frame. I am going to have to buy new front and rear shackles but they cost about $350 for all four of them and will cut out and put new metal in the rusted out area, and plate the weak area on the drivers side. I am wondering if I should just get a different frame. I will be putting a 6'' suspension lift along with 37'' tires on it, and Im wondering if it will hold up with the extra stress that will be put on it.
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