I still think you will find out Paul Hawkins never won a race without a ZF in a GT40.
I'll think you'll find Paul Hawkins never raced with a ZF at all. If he did it was prior to Bernies arrival in Aug 1968.
I thought the Fortification issues # 80 onwards that had the recollections of Bernie Mylon, comprehensively confirmed that Paul Hawkins DID use the Hewland. Bernie is definite, there are photos and he mentions the Hewland in various contexts several times.
Note that Bernie is unlikely to be mistaken or to be confusing another car with AMGT2 as that was the only race car that he worked on in his short time as a race mechanic. He worked for Paul and then went with the car when it was sold to Juncadella. He then returned to Aussie to run the family business.
For more details see the first post here. http://www.gt40s.com/forum/original-gt40s/29294-hewland-lg600-amgt-2-a.html