did you read my link 1J0412311 = a 20mm spacer put it between top mount bearing and the spring plate job done for the front and you can put a 20mm spacer under the spring on the rear job done simple lots of people have do just that come summer time take them out
yes, you can swap stock model springs over and it will raise the car. rear on mk3 pretty much same weight for all but you may find a gti front end is slightly heavier so it may not raise it a full 20mm. All mk3 are wide track regardless of model so no worries there. shocks wont affect the ride height so just use good quality units boge/sachs/bilstien/genuine/etc and lower spec springs. I guess a diesel MK3 would be similar engine weight, or a 1.8. the smaller engines will be a bit lighter so avoid those. VR6 are heavier again but also lower than stock MK3 so may not raise it up the full 20mm you are looking for. only thign to be aware of is there are 2 upper spring sizes for the MK3 front springs for both gti and non-gti models, so you may have to change the spring plates to match. early mk3 non-gti differ to early gti, but late non-gti are the same as late gti (as the later non-gti switched to gti type top mounts) Hope that helps!
