2523 (2507, 2522, 2501) - There were three 250F chassis that used the number '2523'. Let's try to approach them in some order. First will be '2523/1' since it is first with the chassis number 2523 assigned to it by the factory. In 1956, '2523/1' was built up using the frame originally from 2507, the chassis number '2507' having been re-assigned to the new chassis when it was returned to the customer. The damaged frame was repaired and returned to service and assigned the new chassis number 2523. In August of 1956, a new chassis bearing the number 2523 was completed. Therefore, the engine and other running gear were removed and the rolling chassis placed off to the side in the factory shops until some determination could be made as to what to do with the chassis. When a muletto was needed to test the V-12, 2523 was dusted off and the V-12 installed. After the need for testing the V-12 was completed, 2523 was once again rolled off to one side. Originally thought to sold 2501 as 2526, what Keith Campbell actually bought was 2522 after its being used as 2523, with new bodywork similar to that of 2501. In 1958, the chassis was completely refurbished, a 250/F1 engine installed and the car sold to Maria-Teresa di Filippis for the 1958 racing season.
- Then came '2523/2' being the second chassis to carry the chassis number 2523. This was originally thought to be a new car built-up during August 1956. It was intended to serve as a spare car for the works team. And, incidentially, to replace the other '2523' that was being used. Actually, it was 2522 renumbered as '2523' and not a new car as though. At the end of 1956 a car was taken to Australia by the works team - originally thought to '2523', but at this point it got a bit murky. Whatever chassis that went to Australia, it wasn't 2523 or 2522. That Australian chassis may have returned to Modena - at some point - and served as the basis for the rebuilt '2504.' Well, maybe. But, then again
- And lastly, '2523/3' which was chassis 2501 renumbered to become the third chassis to have this number and was the car campaigned by Maria-Teresa de Filippis, not the converted V-12 chassis 2523 - which was originally 2522 - as originally thought. See, isn't this a piece of cake? No problem