To be a kill-joy but I think that cutting the manufacturer's components & then re-welding them together is potentially very dangerous and is probably a MoT fail point.
i think this referes to major suspension components,ie drag links,drop arms,wishbones,trailing arms,etc the bottom link on the p6 is forged/cast as one,any cut"n"shut would invite MOT failure,....i toyed with this idea before,got as far as grinding the weld out of the bottom swivel pillar,cutting 25mm off the bottom,reweld the hub carrier back on,bottom link strut had the ball joint cut off,it was machined,threaded,fitted with a track rod end from a p4 rover(or was it a land rover,can,t remember which),the lower link was a problem i never managed to solve without major expense to me and the small workshop i was running at the time....