Answering some of your questions and comments.
I have a Pfaff Expression 4 with a large throat and built in dual feed. However, I have completed other quilts this large on smaller machines but you do need a lot of table space behind and beside the machine to support the quilt. Trick is to quilt small areas at a time. Glad some of you have been inspired by my basting process, that was my motivation for posting this in the first place. Oh, and I am as 'green' as the next person but my knees and back have always been bad (polio) and just do not crawl on the floor for any length of time. Besides, a few hundred pins in a quilt this size would have driven me mad and would not have given me the results I got with spray basting.
I have been pleasantly surprised at all the attention this posting has received. Thank you one and all!