Welcome to the new and improved Proflex / K2 Tech Forum!
From new the NR4 was fitted upside down on 4000 and 5000 as per Scooters bike and Col has dared to be conventional and fit his the right way up - which is really the wrong way up.... You get it.I remember trying to swop mine around as it does look strange up side down but seem to remember the shock fouled the top mount. That was why they fitted them this way around. Col must have clearanced the top mount area a bit to get his shock that way round? On the subject of your stiff forks, if your not going to service them now it might pay to squirt a bit of grease into the linkage grease ports before you ride it just incase they are dry. These forks run plane nylon bushes not bearings so you don't want to run them dry and wear them or the metal links out. If the forks are greased and free it's probably the shock needs re charging with nitrogen. Chris