[TR] ref: TR4 question (Andrew Uprichard)

[Q]

TR3 and Tr4 use different wheelboxes.  The earlier TR3 use a different 
motor and I think that they all use a different drive gear in the motor.

2 Speed wipers were an option in TR4's but I have not seen a car with 
them installed myself.  It changes the wiring so you should check that 
as well.

I had a TR4 with TR3 wheel boxes and it reduced the sweep of the wipers 
by about 3".

No harm in trying them and seeing how your combination works I expect.

Edward Hamer
Petaluma CA