The 80-90 plus series had a very good front mudguard mounting method a cast alloy plate running on a shell bearing supported the offside mudguard stays. The nearside stays being rigidly fixed to the brake back plate. The only problem is you need another brake torque reaction link on the fork upright. Some forks are fitted with these, all genuine 80-90 plus forks have them. I have newly cast the RHS alloy support and can machine them to take the original shell bearing or for direct fitting to the wheel spindle. Various lengths of stays can be made to suit 18-19-20 or 21" front wheels. I think all original plus were 21", a data sheet on this is available as are close up photos of the set up. The distance of the pivot points vary on the various types and these need consideration. These data sheets can be posted if anybody is interested.
Case converted to upper and lower for readability - Dave, 3rd April, 2010