I think it depends on what you consider "modifications." For some people that means big aftermarket bumpers and huge spoilers.
For me, I like to be in keeping with the spirit of the original design.
All of my modifications (except for splicing in an air horn) are 100% reversible back to stock, however most of my modifications are not flashy exterior modifications, but what I would consider tasteful upgrades. For example, de-ambering my lights, upgrading to a set a 996 rims, or filling up all of my blank dash switches with useable buttons/features. Almost all of the modifications I have done, that you can see, are just 996 parts that I prefer the look of, and most of the modifications or hacks are practical updates you cannot see (clutch switch, iPod adapter, air horn).
