Hi Ian, thanks heaps for your reply/input....ok, got a 4 door auto donor mk1 I got the tunnel out of, is there an exact spec I have to follow when cutting into the firewall? I heard that it should be the width of the block? What happens to my heater box after that? Remount elsewhere?....we have get things engineered here...nightmare, so things have to be done 100% or they won't pass it....there are a few expensive radiator intercoolers in UK....talk about spoilt for choice....lucky bugs.....it would cost me $1500 aus dollars to get one on ebay.....do you know anyone else that makes them specifically for mk1 cosworth conversions?....what do you have on yours?....I dont want to cut the front panel so it's exposed, I want it hidden, don't mind cutting under the bonnet/radiator support etc, but not the front panel....I got so much to ask, but I'll go a little at a time otherwise my head will hurt..........with crossmember where do I cut to and from?.....example, if I mark centre how far on both sides?.....must work now, speak soon hopefully.....fatty