As far as cleanup goes the last SA/SG I got in Feb. was lightly oiled,no grease anywhere, I field stripped it, tightened up the gas cylinder, give the bore a once-over with a brush and cleaning patches,greased up the receiver, and was pretty much ready to go... you might want to look at a muzzel guide of some kind for the cleaning rod, also when you get it check the gas cylinder for play,(sideways,back&forth) most are loose, if it is, you'll have to tighten it up,if you want it to shoot better, look over at www.jouster.com best board for the M1/M1a, click on "Lanes Tips" at top of page, lots of tips you can do yourself (like tigthening up a gas cyl.)lots of info over there, well worth lurking, and don't be afrid to ask questions those guys will help..
Also check and see if stock fits tight, grab it by the barrel(other hand on stock) and see if you can detect any forward or back play, and any sideways play, alot of stocks on these rifles are 50-60 yrs old, and many are oil-soaked, the wood is compressed and the rifle won't lock up tight, you can shim it, (again, Lanes Tips on the jouster board) and make it work, then again maybe you'll get one with a nice stock..... you can never tell... last , READ the manual the CMP sends with it it's well written and will help you alot, lot's of clear pictures, one thing's for sure, you'll love the "CHING" sound as the clip comes out on the last round...nothing like it!!