I have LoBo drive shafts from the 2L DOHC sierra fitted to 4x4 LSD , and the off side shaft seams a bit long, The ? is are all sierra shafts the same ( I know the off side is longer)
eg. Is sierra lobo O/S with ABS the same length as without ABS

There are two different length shafts (for both sides) available, with approximately 1/4inch difference between the two types. However, alledgedly they are interchangable...

Then I have the long ones and they don't fit my Indy

Shouldn't be any length difference between ABS and non ABS. ABS shafts just have a toothed ring added.

There's so much plunge in the CVs (a good 50mm per shaft) that slight differences in length shouldn't matter. Afaik no manufacturer specifies that particular ABS/estate/4x4/etc etc shafts can or can't be used based on any length difference. All i know is that the ABS tothed ring has to be machined off for ABS shafts to fit MK Indy rear uprights.

Liam