Stihl MS271 crank shaft bearings and oil seals

[Clake4341]

Good morning all I have 2 questions on the MS271. I have it torn down and want to replace crankshaft bearings with OEM. should I heat the shaft to remove old bearings than to replace with new freeze the shaft and heat the bearings?? also some articles talk about soft oil seals and hard oils seals what is the difference as the MS271 has a brown and a blue seal  which goes where??

Thanks