You're right, that jig won't work in your case. Too bad, but all is not lost.
I think I found you a solution. This one is about a quarter of the price and has excellent reviews.
It's a universal mini-jig that will enable you to get a perfectly centred pilot hole - absolutely critical for doing this job right.
https://www.amazon.com/OTC-Tools-6982DGS-Drilling-System/dp/B01A8Q3BCE
I hope this one works.
Good luck!