ehmm mods are what ye want really, it doesnt need much doing as theyre lovely looking cars as they are, they are mainly available on ebay tbh id get a set of fog lights for the front of yours
, there are blue monaco seats available for them, but the hatch and saloon seats are different. where are ye based for meets. exhausts theres janspeed and xpower, scorpion do one, piper and you could always get a custom one mad up to whatever spec ya like, the mk1 exhaust is slightly different as its slightly longer but will still fit, dunno if ya have the heatshield for yer rear bumper already so you can fit the exhaust properly