Hard to describe clearly but Plan A was two 2x8 planks laid on top of the stair treads, spaced on center with the dolly casters. The back wheels were to touch first and then as mill was lowered, i knew it would tilt backwards and roll down sort of popping a wheelie ending up almost 45 deg. This would have been fine (Did my BP main casting the same way no prob) once the back wheels made land at the bottom, was going to c-clamp and block the wheels while letting more chain out. This motion would take a bit of grunt to coax it fwd until it was "over center" Well plan worked great until halfway down we realized the Z stepper was going to hit the crane cross bar going down. Plan B was I quick removed the motor but still no love. Too tall to clear. The only option short of completely bailing on the attempt was Plan C to forget trying to roll the wheels on the plank but rather straddle the wheels over one 2x8 and slide the back end of the wood dolly down the wood plank. It worked albeit with great difficulty because the casters would still catch on the crest of each tread and i had to pry with a long 2x4 to get the whole affair to ride over the "humps" then slide 6" to the next tread. Repeat 6x until landfall then heaved it over center onto all 4 wheels.
Not pretty or elegant but its done. Remind me not to move any time soon or it may come complete with a machine shop