had the same problem with my 606. wound up making a tool that easily removes the prechamber [the gp's tip needs to be backed out enough to clear the pc]. i then machined an insert with orings that goes in the pc hole that lets you hydraulically pump[used my poptester] out the gp] works like a charm and doesn't require the removal of the oil filter housing. whunter now has the tool. pictures and an explanation of the deal are posted somewhere in the shop forum.

thanks, joe hunt