Help With P38 Overheating (same old story!)

Hi all, Im looking for help with my P38 V8-the normal overheating problem!- diagnosis and repair. I have no workshop/garage so headgasket/engine change difficult at home. I live in the Ashford/Hythe Kent area.
Would be most grateful if someone could point me in the direction of a decent mechanic who would be willing to help. Cheers