Basic mechanic Q o' the day: install hub dust caps - ever had one that was hard to seat properly?

A piece of pipe or schedule 40 PVC with an inside diameter allowing it to slide over the dome of the cap and butt up against the small "perimeter flange," allowing you to drive it on, without damaging the cap. Once the cap is on, the recessed portion of the cap that went into the hub, should take shape of the hub, however it may be a little stubborn getting it back off to service the hub.
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