What you're probably looking at are an Ammco 7000 "Hustler" (rotor only machine) and either an Ammco 3000 (drum only) or 4000 (does rotors and drums). The tooling for both is interchangeable, so make sure you get the proper adapters for whatever machine you buy (example: if you buy the rotor...
I've done it multiple times via MIG welding.
Clean the old paint off, have a good (clean) ground that's as close as possible to the weld, and then do a series of tack welds. Take your time, and space them out; the key is to keep the motor housing from getting hot enough to melt the...
These guys (www.qsponline.com) are great to deal with; they're heavy duty, well made, and made in the USA.
https://www.qsponline.com/passenger-turnplates.html
Snap-On AN196ANCF; I use these nearly everyday, and consider them to be both durable and extremely nimble.
https://shop.snapon.com/product/Needle-Nose/8%22-Long-Nose-Pliers-with-Cutter-and-Side-Fastener-(Red)/196ANCF