Matching those grinds exactly scares me.
Not that critical. Weld up the grooves, leave some of the original contact surface alone. Grind the weld down to the level of the original surface. A hand-held angle-grinder would be fine.
If you wanted to be really fancy
, you could center-punch some divots into the ground-down weld material, to kinda mimic the "texture" of the original contact pads. Then touch the divots with the grinder again, to knock-down the high spots. The pads are embossed so they hold a little grease.
The rear disc conversion kits scare me also.
Good. Proud of you. I don't doubt that there's GOOD disc conversions; but the bottom-feeder "Flat Brackets" get all the publicity here.
A full 800 upgrade is the only long term solution in my mind
Wise, from a performance/price consideration.
"I" would keep the drums unless pretty-much everything
was worn-out--backing plates, drums, shoes, hardware, wheel cylinders. But that's me.
The reason I need another donor truck is because I already bought an 04 4x4 dually sight unseen as the donor truck for the entire brake system. It was supposed to be a rust bucket, and had been parked for two years in a field, and it was cheap cheap. But after some simple fixes, it fired right up, shifts and drives. It is the LLY duramax, alison 6 speed, and is a Centurion. It appears to not be a donor truck after all, unless the frame doesn't pass muster.
nice. There's your "heavy-duty" tow and work vehicle, so brake upgrades on the other truck become less critical.
I did something like that once. Bought a '93 Lumina as a "parts car" to fix crash damage on a '92 Lumina. Both had the "big" (Ha. Frickin' six-popper. But at least they're 4-valve DOHC) engine, the sport suspension, and both had the same paint code
. The silly thing ran so good that when I was done robbing fenders, hood, steering column, bumper cover, etc...I had to flip the crash-damaged parts upside down on the lawn, and jump on them to push the dents mostly out. Went to the Treasure Yard for a bumper cover and steering column. Then I put the rumpled parts onto the parts-car and drove it for ~50K miles until the head gasket popped.