I have the FLM 1/8th bulkless, and I would probably advise against it. I bought the 8-spyder gear set from UE, and the shafts are too big for the bearings, so i had to assemble the diffs inside the bulkless (drill a hole in one side so i could screw the ring gear screws down. I them siliconed up the hole. It was a pain in the ass, and the FLM bulkless arent the best of quality. There are small gaps in the case, so a thin coat of silicone should do it. I haven't gotten a chance to test mine out for more than a few minutes of break in though.