They fit with just a bit of work and maybe some fabrication.
Is the switch mechanism complete? It should come with a flat metal inner half-circle collar which helps the outer clamping piece hold it to the steering column.
Did you grab the column and shaft as well? The VW column will probably need to be lengthened. The later columns were a good deal shorter than the early columns as the later blinker switches were around ten inches or so and included the dash mounting piece as well.
You'll also need to scoop up a mounting rubber donut and under dash clamp, although the sweet aliminum one from the 356A or an aftermarket one will work fine.
The steering wheel mounts a little differently with an early blinker switch, and of course, used a different steering shaft as well. The early steering wheels sat partially inside the switch. They nestled inside the upper area and bottomed out on an outwardly tapering collar at the top of the shaft. If you're going to use a later shaft, you need to change the steering column upper bearing and lower the blinker switch on the column a bit to accomodate the later wheel. You'll have to use the earlier wheel cancellation ring and figure out a horn contact, since the early set-up had it in the column (on the side) not at the top of the blinker switch/mechanism.
All sound complicated, but it's easy as pie once you have everything apart and start mixing and matching components.
Luck!
TC
