Tricks to change rear DS spark plugs with cheap headers.

I'm regretting buying the cheap patriot headers more and more as time goes! I want to do a compression test and change plugs as part of my efforts to make it run to it's potential. Does anyone have any tips or tricks to remove those rear drivers side 2 plugs a little easier? Has anyone made a wrench to do the job? Any help would be appreciated.

The car is a 74 Duster with a 360, power brakes and Patriot headers. I'll look for a photo.

Cley