Hi Mike,
Here is a picture of the backside of a 1600 101/105 pump I just rebuilt. Probably much like your 2 L. As you see the seven holes are for 7, 6 x 100 threaded studs on the 1600's. As the design is the same, or studs have been replaced by the CORRECT length bolts, they will still be 6 x 100 as Jim stated. If you need more pictures, let me know, I've a disassembled race engine sitting in my..... study
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