Just bought a new corsa breeze hi-torq 1998 1.4 model today. Will be picking it up at the weekend but unsure as to what comes as standard on this model and what is classed as a modification? It has a spoiler-style trim and lexus lights. Obviously the lights are modified but what classification does this come under for the insurance? And is the spoiler standard on this model? Thanks!

if it's not standard, it's classed as "modified" it's best to be as honest as possible or your insurance will be void.

Yes I know the lights are modified but don't know what category they come under for the insurance. And as for the spoiler trim I think it comes as standard but just wanted verification on that

As Jawide says you must tell the insurers exactly what has been done and make sure they record it on the documents or they can just deny knowledge of mods and reject any claims. Hopefully you won't have any but better safe than sorry.

When you insure you will be asked the details regarding the car (generally you input the reg no. and it will find all these details automatically), then you will be asked about any modifications. It is vitally important to get these right, something as simple as the lights being changed can be the difference between a payout and no payout. The insurance companies are a business and are looking to make money, as such, following an accident etc they are looking for any excuse not to payout.
In my experience (as a young driver) having lexus lights and a bonnet scoop (fitted when I bought my car) added 30% to my premium and it was far cheaper to buy original parts from the scrappy than pay the extra.
Do your homework and check various comparison sites before insuring.