Rewelding it id a waste of time and money considering how cheap another stock one is..
Its the heat cycles that kill them.
Do you get in the car and give it a hard time straight away or let it warm up first? If you even give it a hard time!
Yep.If you look at how trans cooler thermostats work they don't block the flow, they just allow it to bypass the cooler. Its exactly the same as an engine oil cooler thermostat. They don't block the flow of engine oil. That would be silly
The runner size difference is minimal, unless its the na head, which is noticeably smaller.
The lifters are pretty obvious but the vct allen head grub screw rather than bolts and lack of vct oil drain on the side of the head is obvious from a distance.