Thanks for reply Bryan and yes use studding as you imagine, 8mm should work fine releasing one side then the other. Note that after stub axle is resting on lower cross tube there may be some residual compression in main spring but you can usually just wiggle it out, and back in again later.
Be careful re-engaging oiler bolt. The kingpin thread is quite fine with posssibility to cross thread. A short tapered drift used to align all the parts it fits through is ideal but others manage with a screwdriver or hex key as large as will fit, taking care not to damage threads.
