As suggested by other MM non-treated maple neck owners : dish washing liquid mixed with warm water (the pink stuff in the bowl on the picture) and an old cotton tshirt.
I dipped a piece of tshirt in the soapy water, wrang it out to not over-wet the board and went ham on the neck
Immediatly dried as I went with other pieces of tshirt to avoid getting the FB too wet. I did get lucky as the crap didn't get too much into the pores and didn't have to sand it. If you look closely at the picture, you can still see some gunk but I'll leave it like that as I feel it's ok for a 30 year old maple neck and I don't want to go sanding it down After doing that to the entire neck front and back, I let it sit overnight to dry then applied a tiny bit of camelia oil with more old tshirt to rub it in. Wiped almost immediatly to remove any excess. Now after it's smooth as butter
