I would put it together first, and not wash until the quilt is finished.
This way you won't have to worry about distorting the blocks or fraying :D:D:D

I agree with soaking it in oxyclean or whatever. I would also put a color catcher in with it especially if there are reds.

DO you really have great results with soaking out stains with oxy clean - I like it in my rug shampooer - but i have never really had luck using it to get out stains on fabric.

I use hot water as directed - but stains never really come out like they do on TV

I would soak them in the tablets for dentures they work great for a lot of things. When I bought this house the toilets had black in the bottom so when we went back to our other house I would put 3-4 teb in there and when we moved up here the stain was gone.

I have friend...same problem and Oxiclean did NOT work ..I suggest a peroxide Q-tip test on one spot and might try lemon juice and salt, then sun drying to sun bleach the muslin. Anyone else tried this?

My mother used salt, lemon juice and sunshine a lot. My 'go tos' are original Dawn, Oxiclean and Carbona.