I have a question..
On yer house plans, do you have a garage attached to the house? Is it alongside it at one end?
IF hat is the case, what I did with mine was to install one of those folding stairways in the garage. Lots bigger than one of those access panels ya can't get nothing thru very big.. And then you have to be a gymnast in order to get in and back out...
I love my folding spring loaded stair opening and have used it a bunch, especially when running duct work and easy access to add those extra 15 inches of insulation on top of the four or five that was already there..
Just wondering if that is an option for ya....