It has a custom shock length has anyone just added a 190×40 shock and it just works? I can't see it would make much difference except slightly chang geometry.

advice appreciated

What's the original length/stroke?

Can cause fouling, change geometry…

Standard length shock FSR XC 2007, 7" X 1.6" or 177.8mm X 40.64mm,
Closest Fox 'off the shelf' 7.5" X 2" or 190mm X 50mm.

The replacement would steepen head angle giving twitchier handling and also raise bottom bracket giving a higher centre of gravity.

It will fit and not foul as the extra length of the shock will allow for the increase in stroke length and you will get more travel however, the handling maybe comprised.

Hmm cheers for the advice…yes 190mm x 50mm seems closest, how much steeper it makes the head angle is the question. The bike already has 130mm rev u-turns on so it's a bit slacker anyway.

becoming a bit of a bastard bike!