Can anyone offer some advice as to how to get these fork seal caps unscrewed on my 1971 DT1-E?
They are on super tight and can't get 'em to budge - and don't wanna bugger up the chrome trying to hold/clamp 'em.
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Not done mine for 50 years but any clamping would just make them less likely to undo.
My ways are rough but so is my bike so don't follow me!!.
But nowdays i might hollow out some wood & cut it into equal parts then lay fine emery in the curve & then two G clamps or bolts across each end so the clamping isn't direct--but indirect. Then fingers crossed she'll unscrew. Am i being rediculous--i dunno--i'm good at rediculous sometimes.
Ya talking the early forks i gather--like my "68 forks.

I wonder if one of those nylon strap wrenches would grab the chrome and not scratch.

www.amazon.com/Filter-Strap-Wrench-Remover-Socket/dp/B079KCDBRS

I use a vice magnetic V groove soft jaws for years with no problem. A strap wrench would probably work too as Schu said 

I use a strap wrench.