A 603 will fit. There are a couple of threads about doing it to an R107. Of course, isn't a later diesel full of those electrical do-dads too?

The relay you're looking for is behind the kick panel by the passenger's right foot. There are several ice cube relays. One of them is for the fuel pump.

For these old D-jet motors, you're going to want to plumb a fuel pressure gauge that can accurately read 0-40psi in place of the cold start valve. You are shooting for 32psi the moment you turn it the key and it should stay there a while after you turn the car off. There are plenty of diagnostic threads in the veterans section with similar advice.

Good luck.

-CTH

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