Firstly what frame does the 98 M600 have ie same as 851?
I have a set of rearsets from what I think an SS.
Looking for suggestions on how to mount as there is no option for mounting the low exhaust.
have found a set of 851 of exhaust hangers but unsure whether they will fit  my frame.
Any suggestions or options
thanks

Excluding the S4 Monster frames are the same, except for some minor changes through 2001.  They are based on the 851.  If the rear sets you are using are from an SS they will be very high unless you make adapters.  No idea about the 851 exhaust hangars.  Not cheap, but  http://www.monsterparts.com/p/PE201/Rizoma+Rearsets+for+Ducati+Monster+M600-1000.html

Like he said. The SS ones fit but wlll be high.

As for mounting the low level exhausts.
You'll be looking at making brackets.
Or get high level exhaust.

These are the rearsets that i have acquired.
Does anyone recognise them or have comments on their suitability.
Also if low mount brackets are not commercially available would anyone have a template i could copy

thanks

Those look like OEM SuperSport rearsets.