Well, I kinda gathered, just didn't know what made you make the connection.
Years ago, I used to have an MG, and my dad had an Austin Healey 3000.
Reading the English repair manuals, with their own special terminology, was entertaining.
I guess they needed to be entertaining, to make up for the bass-ackwards (positive earth) electrical systems.
That can make anyone want to throw a 10mm spanner right through the window!!!

 

I have added anti-freeze, which is blue. But the liquid seems to be clear to white in colour. Will have to take a look next time i get the car out, not been able to use the Camaro much at the min due to the bad weather.
Not hered of that car program you were on about, i watch American hotrod and west coast customs.

 

Never heard of Wheeler Dealers either, so now it makes sense.
Back to the OP though. I can't imagine what might be routed on that side that would show up clear, if you've got blue antifreeze.
Is your fluid level in the radiator keeping up, or do you have to top it off occasionally? If you have to top it off, then I'd guess it may still be coolant from the heater core.
Do your indows ever fog up when you turn the defroster on? If so, it's surely a heater core leak.
Have you felt the carpeting to see if it's damp under the heater vent, or if there's any moisture in the heater vent?

 

I have had to refil the radiator header tank twice in the last 2 months and yes the windows do fog up quite abit. Not seen any moisture from the vents or on the carpet. But that might be because i dont drive the Carmaro to much.
It looks like i need to remove the box to investigate the heater core, is there anything to watch out for? before i remove it

Thanks from Luke

 

I love that show. Those two clowns crack me up. The fat guy buys the cars and sticks the tall skinny guy with all the work.

 

It's a huge pain to remove the heater box/core, but it needs to be done to get the problem solved. Drain the radiator and pull the heater hoses first. There's nuts out under the hood that sandwich the inner and outter portions of the box together. The ones that are back under the pass. side fender are not accessible without removing the inner fender panel. Once the inner fender is unbloted you can pry it down out of the way, then the last bolts can be removed.
After that you go inside and pull the heater box off the firewall you can remove the clips that hold the core and pull the core out. Then just drop the new one in and replace everything in reverse.
It was an all day project for me the first time I did mine, but I cut my outter heater box in half vertically and made it so I could remove the core half later if I ever needed access again. I welded on a thin piece of sheetmetal at the joint to overlap the two halves and put thin self adhesive foam on the joint.
Since I've had my Camaro for 38 yrs. I did have to replace the heater again last year, and it took all of two hours the second time!

 

Removed the heater core box today and it's clearly at fault. Next i need to locate a replacemet part from the Uk which may be a little tricky.
Thanks for all your help