Head gasket failure on Blue

I'm quite certain that Blue's head gasket has failed. I put some Bars Flush in the radiator to clean the cooling system out. After that Blue started running like a bag of spanners at low revs (below 2500 rpm) and clouds of steam are coming out of the exhaust. Today I drained the radiator, refilled with plain water to flush it out, went to Champion to get some fresh antifreeze & Bars Leaks, drained the radiator again, fitted the new thermostat and refilled with fresh coolant. It looks like I'll be ordering a head gasket set. I'll get Brian to do the job. The last time he did it for me on a Ford Sierra Sapphire which was 10 years ago. 2 years prior to that I had a head gasket done on another Ford Sierra so this is the third time for me. I'll get the timing belt changed at the same time as it is overdue and I've never done a timing belt change on any of my Acclaims. This means Brown will have to be put back into service. I hope I win some of my eBay items then I can get on with sorting out this car.