we did a test with brake cleaner inside the chassis where it wouldn't show if it reacted with the paint. all good so we set to with clean cloths and got the yellow paint much better looking. we did the chassis and crossmember too, not just the bulkhead because it was easy without the engine in there. i've added before and after pics, it's much brighter now.
then we swung the engine and box into place and that's where we are now. it's all bolted up tight. oh, the headers fitted in with plenty of room so that saved time as well as their gaskets having a much better chance of not ever blowing.
neil.