I just used standard wires that are slightly larger than the OEM wires. At the solder points, I used half of the wire strands from the aftermarket wires, so that the solder point thickness has similar size as the whole wire. That can eliminate resistance. These sensors are very sensitive to resistance.
I once had oil in the MAF and I just used brake cleaner to clean it, then I used pressurized air at low psi (about 40 psi) and blew it clean. I didn't have issue with it. However, I heard that someone cleaned it (i don't know how he cleaned it) and he ruined his MAF.