Don't know what tubing your frame is (Steel i know...) but setting 531 with the sheldon method works a treat, remember it's springy stuff so you might move it a good 50mm to achieve 2mm set.. remember to keep measuring in between levering so that you know how much each stay has to go. Get that bit right and you don't need to fuck around with alignment too much, (I'm quite satisfied by just tweeking the track ends with a big wrench and doing it by eye). By the way 120 to 135mm you will definitely need to re-align the track-ends! Bigggg bit of wood and be brave!!
Don't know what tubing your frame is (Steel i know...) but setting 531 with the sheldon method works a treat, remember it's springy stuff so you might move it a good 50mm to achieve 2mm set.. remember to keep measuring in between levering so that you know how much each stay has to go. Get that bit right and you don't need to fuck around with alignment too much, (I'm quite satisfied by just tweeking the track ends with a big wrench and doing it by eye). By the way 120 to 135mm you will definitely need to re-align the track-ends! Bigggg bit of wood and be brave!!