I recently swapped my trailing arms to some stock Vaterra Twin Hammers arms. I drilled a hole clean through them and through-bolted the swaybar links, but they just bolted up otherwise. Of course, I had to make new upper links too. I cut the stock rear driveshaft down, but it ends up not having much spline engagement at full droop and will likely need to be replaced with something different. The tires just barely clear (2mm-ish) the side portion of the cage that extends behind the cab, but they left some rub marks on the cage after a run (tire expansion.)
The truck definitely handles differently. I've only run 2 packs through it on the street, but the rear end is significantly stiffer now that there is less leverage on the springs, which is a good thing, but maybe a little too much of a good thing. Some slightly softer springs may be in order.
The other issue I came across was stuffing the big 7400mah 3s in there. I normally compress the rear suspension a little and it slides right in, but the angle of entry is much steeper now that the axle is nearly 1 1/2" closer to the rear bulk head. The Metal Concepts axle truss is right in line with the battery door too, so that wasn't helping. My solution was to trim off the 1/4"ish plastic pieces on the bottom of the chassis, directly under the battery door, then file a radius on the lower corner of the Metal Concepts truss clamp. Now the battery fits, though it's still tight getting it in.
The whole goal here was to shorten the truck to a point where a standard short course body would line up without looking ridiculous, and for that, it worked perfectly. The Baja Rey is now nearly identical in wheelbase to a Slash and that opens up a ton of body options. I'm still working on fitting a Proline '78 Chevy stepside body on it. The back end of the cage sticks out a fair amount past the SCT sized body, but with some creative modification I'm hoping it will pass as a bumper. On this particular body I can't really trim it in a manner that would sit down low enough for the cab to be tight to the cage, so I'm going to smoke the windows and let the cab sit a bit higher than the cage. A stock Slash body can sit down pretty low with minimal trimming. Front and rear fenders look great right where they are. There's already holes molded into the stock cage in the ideal spots for body posts, so mounting with 4 body posts/clips will be my method.
If this all comes together in a manner I'm happy with, I'll either buy nice VTH arms with replaceable rod ends (so I can add a mm or 2) or spend the extra to have JEC make custom short Baja Rey arms... we'll see.
