Well it sucks that you had to mess with all that. But you've got some good welds on it and you know about them, so you should be fine. And 3000 and it runs ok - you're still on the plus side of things.
Good luck with it !!

 

I used to work for a Heat Treating shop that worked in metals
Heat Treating is performed on welds to relieve stress, to make springs "spring" etc
It was years ago but basically had the understanding that any weld needed to be heat treated to relieve the stress
Possibly wrong but hopefully someone else can jump in & tell me I'm wrong/partially right or whatever

I did have a shop weld lug nuts to a brake drum on a 66 Mustang around the same time
Not stress relieved
3 of the 5 lug nuts sheared off....luckily at low speed, no accident