Dual valve springs stock on 2.02 915 J Heads?

You'll be OK for coil bind with the single spring IF you install it at 1.7. But just because the spec sheet for the spring says 1.7, does not mean it will install there. That depends on the retainers and valve. Stock retainers & valves install at around 1.650" IIRC. If that was the case, then the compressed height at max lift would be past coil bind so that does not work. You either change retainers or locks, or deepen the valve spring pocket , or a bit of both.

BTW, IMHO, .035" is a bit close on coil bind. I'd shoot for .060".