A Top Gear fanatic has completed the ultimate motor challenge - building a £5million supercar with scrap and spare parts. Amateur mechanic Jacek Mazur, 48, made his own replica McLaren F1 for just £20,000 - 250 times cheaper than the real thing. He even paid tribute to his favourite TV show by building a tiny rear seat for Top Gear co-host Richard Hammond. His previous projects have included building his own Lamborghini and a Porsche - but the British-designed McLaren F1 has been his 'ultimate' success. They can fetch unbelievable sums and in August this year one sold for a staggering £5.1million at classic car auction Gooding & Company.