I have always run my 4RT with 10mm spacers on the mudguard with no problem at all. Bit concerned that you're not using the fire proof cage though as I know of someone who removed that part on the Sherco and melted the filter due a 'Spit Back' through the carb !!!!
If you get stuck for the correct rods try Sifbronze Magnesium No:23 it comes in 3.2mm rods and you can buy them in 1kg packets. I've used them many times welding castings etc.
Good Luck
When you screw the adjusters (clockwise) generally on all Ohlins dampers this then stiffens the damping. Anti-clockwise the opposite. With your weight be careful not to reduce the rebound too much as this will effect the grip level when riding very slippery conditions. Good luck
