I am currently put a 13bt and h55 into my 76 FJ40. To start with I have two questions. In making the engine and transmission mounts with a buddy. We haven't been able to get the output flange directly inline with the differential flanges. So I'm no expert about driveshafts but I assume you need to get it as close to in-line with the diff flanges as possible. We've moved the tranny/engine combination as far forward as I would like. The driveshafts have Ujoints on both ends, so I assume they are designed for both vertical and horizontal alignment differences. But how much and at what pitch should the drive shaft sit at? Any advice would be great. I know the pitch will also change once all the engine/tranny weight is on the frame. Next problem, does anyone have any advice on hooking up an air filter for one of these. The 13bt is an 85, red block. I have an air filter setup from an 87 mini truck. But I see it has some kind of valve system with wiring on it before the air goes into the filter. Does anyone have any advice on the best setup for my situation? I will try to give G and S a call tomorrow. Thanks I posted this message in the FJ40 section as well.