I have been doing the same build, with complete engine. Getting the subframe turned into an epic disaster.
I also, am glad mine is coming together.
This 'disaster' I don't understand, the subframe (or kframe) does not need to be changed, the part number for this is dictated by the engine. If you're not changing the engine then you can keep your B4 (or Mk3) tdi K-frame and just replace everything attached to it. The Plus suspension stuff attaches to it just the same as what was there for 4x100 base.
In order to change the front suspension on any Mk3 or B4 from 4x100 to 5x100 you only need the following:
1. Front control arms from 6 cylinder car
2. Spindle aka bearing carrier from 6 cylinder.
3. Steering rack or just replace tie rods with those for ZF rack.
4. Axle shafts (or actually just the outer CV joint if you can't find)
5. Brake calipers and carriers from 96/97 6 cylinder car..
6. Front sway bar (and end links) from 6 cylinder car.
There is a difference in the brake calipers between the 256mm and the 288mm brakes but the piston size is the same. The caliper carrier needs to come from the 6 cylinder car too.
The rear is even easier, at least for stock components.
1. Rear rotor (with integrated hub) from 6 cylinder (5x100)
2. New bearings / races for new rotor.
That's all you need to do at the rear of the car, just change to the 5x100 rotors, everything else is the same between the base and Plus suspension cars in the back. If you have ABS (rare on base suspension) be aware you need to get rotors with the ABS ring or buy separate rings and install them.
All these components can come from 6 cylinder Passat, GTI VR6 or Jetta GLX. The suspension parts can come from 94 up to early 99 models, the brakes have to come from 1996-97 Passat or 1996-99 Mk3 VR cars.
This is literally all you need to do to change from the 4x100 to the 5x100 setup. I'm pretty sure it's a complete list but I do make mistakes.
While the list of stuff isn't all that long the problem now is that so many of the donors have been crushed and pulverized that it's tough to find the parts even in the JY world. I'm still seeing a few Mk3 2.0 cars but 6 cylinder Passat or Mk3 is few and far between.
Steve
