Guys,
Thank you for the responses. I know the question may seem trivial but after all the work that I've put into this car, I'd hate to screw it up.
I've not had any luck with the aircraft stripper on the 2K primer. So, based on the above advice, I think that I'll try and score the surface with 40 grit until I get into the lower layers then try the chem strip again.
Thanks again.