even your mum may find it hard getting a good deal or even finding a policy at all that allows a roll cage and an engine conversion. Some insurance companys wont even allow an induction kit. and the type of policy that will allow the cage etc etc may not be hot on having you as a driver on it 2. you could prob get £500 for your car as it is. The conversion will cost you about £1000 realistically, becuase you will be paying someone to do most of the labour and theirs always parts you need etc etc etc. so you could spend all this money on a mk4 escort and pay the same again for insurance, or get a car that is pretty quick in the first place (a 1.8 zetec in a mk4 escort wont be as fast as you prob hope)
get a mk3 fiesta rs1800 or an xr2 or something with the power etc in the first place all done and dusted and wont be a pain to insure. Seriously get the insurance homework done. What happens if you do the conversion then phone about and cant get covered??? Or the only cover you get is £1500 ??? surely half an hour of phone calls will put your mind at rest.