anti-roll bar question

[polonuts]

anyone know the diameter of a MKIII squareback boulevard on an L plate anti-roll bar. I am going to update to poly bushes, but have been given the choice of:

18mm
20mm
22mm

I am also in need of measurements for a bumpstop set I have 5 options:

overall length outside diameter c-bore
33mm 49mm 20mm
38mm 39mm 13mm
61mm 39mm 13mm
78mm 39mm 13mm
48mm 49mm 20mm

TBH I don't have a clue