As above:

Will golf mk5 rear springs fit FL Octy VRS

Got an -50mm H&R Cup kit on my Octy but the back end sits quite high for some reason, got a chance of getting some used Mk5 Golf coilovers with intention of using the rear springs and adjusters just to bring it down by another 10mm or so

Cheers

It will physically fit but it may not be the right spec as the golf rear end will be lighter compared to the octy rear end.

as above, dimensions are fine but it'll prob have different spec spring. with the coilover adjuster you'll prob be able to get it to sit ok but you may find once loaded up it will drop more than a specific octy rated spring.